N-acetyl aldosamines, N-acetylamino acids and related N-acetyl compounds and their topical use

Abstract

Compositions comprising N-acetyl-aldosamines, N-acetylamino acids, and related N-acetyl compounds are useful to alleviate or improve various cosmetic conditions and dermatological disorders, including changes or damage to skin, nail and hair associated with intrinsic aging and/or extrinsic aging, as well as changes or damage caused by extrinsic factors. N-acetyl-aldosamines, N-acetylamino acids, and related N-acetyl composition may further comprise a cosmetic, pharmaceutical or other topical agent to enhance or create synergetic effects.

1. A composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one compound selected from the group consisting of N-acetyl aldosamines, N-acetylamino acids, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof,
 wherein said N-acetyl aldosamine has the formula:   
       
         
           
           
               
               
           
         
       
       wherein n is an integer; R 1  is selected from the group consisting of CHO, CONH 2 , and COOR 3 ; R 2  is selected from the group consisting of H, I, F, Cl, Br, and an alkyl, alkoxyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form having 1 to 19 carbon atoms; R 3  is selected from the group consisting of H and an alkyl, aralkyl, or aryl group having from 1 to 9 carbon atoms, 
       wherein said N-acetylamino acid or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycine, N-acetyl-alanine, N-acetyl-valine, N-acetyl-leucine, N-acetyl-isoleucine, N-acetyl-serine, N-acetyl-threonine, N-acetyl-tyrosine, N-acetyl-cysteine, N-acetyl-methionine, N-acetyl-aspartic acid, N-acetyl-asparagine, N-acetyl-glutamine, N-acetyl-arginine, N-acetyl-lysine, N-acetyl-histidine, N-acetyl-phenylalanine, N-acetyl-tyrosine, N-acetyl-tryptophan, N-acetyl-β-alanine, N-acetyl-taurine, N-acetyl-r-aminobutanoic acid, N-acetyl-hydroxyproline, N-acetyl-canavanine, N-acetyl-hydroxylysine, N-acetyl-cycloserine, N-acetyl-homoarginine, N-acetyl-norleucine, N-acetyl-norvaline, N-acetyl-homoserine, N-acetyl-methylserine, N-acetyl-hydroxyvaline, N-acetyl-ethionine, N-acetyl-methoxinine, N-acetyl-β-aminoisobutanoic acid, N-acetyl-homocysteine, N-acetyl-cysteine sulfinic acid, N-acetyl-homophenylalanine, N-acetyl-homotryptophan, N-acetyl-5-hydroxytryptamine (N-acetyl-serotonin), N-acetyltryptamine, N-acetyl-ornithine, N-acetyl-citrulline, N-acetyl-argininosuccinic acid, N-acetyl-dopa, N-acetyl-3-iodotyrosine, N-acetyl-3,5-diiodotyrosine, N-acetyl-3,5,3′-triiodothyronine, N-acetyl-thyroxine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-cystine, N-acetyl-homocystine, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof, and N-acetyl-glutamic acid and isomeric or nonisomeric, free acid, lactone, amide, or ester forms thereof. 
     
     
       2. The composition of  claim 1 , wherein said N-acetyl aldosamine or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycerosamine, N-acetyl-erythrosamine, N-acetyl-threosamine, N-acetyl-ribosamine, N-acetyl-arabinosamine, N-acetyl-xylosamine, N-acetyl-lyxosamine, N-acetyl-allosamine, N-acetyl-altrosamine, N-acetyl-glucosamine, N-acetyl-mannosamine, N-acetyl-gulosamine, N-acetyl-idosamine, N-acetyl-galactosamine, N-acetyl-talosamine, N-acetyl-glucoheptosamine, N-acetyl-galactoheptosamine, N-acetyl-mannoheptosamine, N-acetyllactosamine, N-acetylmuramic acid, N-acetylneuramine, N-acetylneuramin Lactose, N-acetyl-glyceraminic acid, N-acetyl-erythrosaminic acid, N-acetyl-threosaminic acid, N-acetyl-ribosaminic acid, N-acetyl-arabinosaminic acid, N-acetyl-xylosaminic acid, N-acetyl-lyxosaminic acid, N-acetyl-allosaminic acid, N-acetyl-altrosaminic acid, N-acetyl-glucosaminic acid, N-acetyl-mannosaminic acid, N-acetyl-gulosaminic acid, N-acetyl-idosaminic acid, N-acetyl-galactosaminic acid, N-acetyl-talosaminic acid, N-acetyl-heptoglucosaminic acid, N-acetyl-heptogalactosaminic acid, N-acetyl-heptomannosaminic acid, N-acetyl-N-acetylneuraminic acid, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof.  
     
     
       3. The composition of  claim 1 , wherein said cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, and changes associated with aging of skin, nail and hair, conditions and disorders which include dryness or loose of skin, nail and hair, xerosis, ichthyosis, palmar hyerperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin as well as diminished levels of such components in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair lubricants and luster, dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair. 
     
     
       4. A composition comprising:
 (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders,   (B) a therapeutically effective amount of at least one compound selected from the group consisting of N-acetyl aldosamines, N-acetylamino acids, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof, wherein said N-acetyl aldosamine has the formula:   
       
         
           
           
               
               
           
         
       
       wherein n is an integer; R 1  is selected from the group consisting of CHO, CONH 2 , and COOR 3 ; R 2  is selected from the group consisting of H, I, F, Cl, Br, and an alkyl, alkoxyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form having 1 to 19 carbon atoms; R 3  is selected from the group consisting of H and an alkyl, aralkyl, or aryl group having from 1 to 9 carbon atoms, 
       wherein said N-acetylamino acid has the formula: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is H or an alkyl or aralkyl group having 1 to 14 carbon atoms; n is an integer; R 2  is OH, NH 2  or OR 3 ; and R 3  is an alkyl, aralkyl or aryl group having 1 to 9 carbon atoms which may be saturated or unsaturated, straight or branched chain or cyclic form; H attached to a carbon atom may be substituted by I, F, Cl, Br or an alkoxyl group having 1 to 9 carbons; and R 1  may carry OH, SH, SCH 3 , COOH, NH 2 , CONH 2 , guanidine or heterocyclic group, 
       and wherein said N-acetylamino acid is not N-acetylcysteine or a derivative thereof, and
 (C) a cosmetic, pharmaceutical or other topical agent. 
 
     
     
       5. The composition of  claim 4 , wherein said N-acetyl aldosamine or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycerosamine, N-acetyl-erythrosamine, N-acetyl-threosamine, N-acetyl-ribosamine, N-acetyl-arabinosamine, N-acetyl-xylosamine, N-acetyl-lyxosamine, N-acetyl-allosamine, N-acetyl-altrosamine, N-acetyl-glucosamine, N-acetyl-mannosamine, N-acetyl-gulosamine, N-acetyl-idosamine, N-acetyl-galactosamine, N-acetyl-talosamine, N-acetyl-glucoheptosamine, N-acetyl-galactoheptosamine, N-acetyl-mannoheptosamine, N-acetyllactosamine, N-acetylmuramic acid, N-acetylneuramine, N-acetylneuramin Lactose, N-acetyl-glyceraminic acid, N-acetyl-erythrosaminic acid, N-acetyl-threosaminic acid, N-acetyl-ribosaminic acid, N-acetyl-arabinosaminic acid, N-acetyl-xylosaminic acid, N-acetyl-lyxosaminic acid, N-acetyl-allosaminic acid, N-acetyl-altrosaminic acid, N-acetyl-glucosaminic acid, N-acetyl-mannosaminic acid, N-acetyl-gulosaminic acid, N-acetyl-idosaminic acid, N-acetyl-galactosaminic acid, N-acetyl-talosaminic acid, N-acetyl-heptoglucosaminic acid, N-acetyl-heptogalactosaminic acid, N-acetyl-heptomannosaminic acid, N-acetyl-N-acetylneuraminic acid, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof. 
     
     
       6. The composition of  claim 4  wherein said N-acetylamino acid or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycine, N-acetyl-alanine, N-acetyl-valine, N-acetyl-leucine, N-acetyl-isoleucine, N-acetyl-serine, N-acetyl-threonine, N-acetyl-tyrosine, N-acetyl-cysteine, N-acetyl-methionine, N-acetyl-aspartic acid, N-acetyl-asparagine, N-acetyl-glutamic acid, N-acetyl-glutamine, N-acetyl-arginine, N-acetyl-lysine, N-acetyl-histidine, N-acetyl-phenylalanine, N-acetyl-tyrosine, N-acetyl-tryptophan, N-acetyl-proline, N-acetyl-β-alanine, N-acetyl-taurine, N-acetyl-r-aminobutanoic acid, N-acetyl-hydroxyproline, N-acetyl-canavanine, N-acetyl-hydroxylysine, N-acetyl-cycloserine, N-acetyl-homoarginine, N-acetyl-norleucine, N-acetyl-norvaline, N-acetyl-homoserine, N-acetyl-methylserine, N-acetyl-hydroxyvaline, N-acetyl-ethionine, N-acetyl-methoxinine, N-acetyl-β-aminoisobutanoic acid, N-acetyl-homocysteine, N-acetyl-cysteine sulfinic acid, N-acetyl-homophenylalanine, N-acetyl-homotryptophan, N-acetyl-5-hydroxytryptamine (N-acetylserotonin), N-acetyltryptamine, N-acetyl-ornithine, N-acetyl-citrulline, N-acetyl-argininosuccinic acid, N-acetyl-dopa, N-acetyl-3-iodotyrosine, N-acetyl-3,5-diiodotyrosine, N-acetyl-3,5,3′-triiodothyronine, N-acetyl-thyroxine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-cystine, N-acetyl-homocystine, and or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof.  
     
     
       7. The composition of  claim 4 , wherein said cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, and changes associated with aging of skin, nail and hair, conditions and disorders which include dryness or loose of skin, nail and hair, xerosis, ichthyosis, palmar hyerperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin as well as diminished levels of such components in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair lubricants and luster, dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair. 
     
     
       8. The composition of  claim 4 , wherein said cosmetic, pharmaceutical, or other topical agent is selected from the group consisting of agents that improve or eradicate age spots, keratoses and wrinkles, local analgesics and anesthetics, antiacne agents, antibacterials, antiyeast agents, antifungal agents, antiviral agents, antidandruff agents, anti-dermatitis agents, antihistamine agents, antipruritic agents, antiemetics, antimotion sickness agents, antiinflammatory agents, antihyperkeratolytic agents, antiperspirants, antipsoriatic agents, antiseborrheic agents, hair conditioners and hair treatment agents, antiaging and antiwrinkle agents, sunblock and sunscreen agents, skin lightening agents, depigmenting agents, vitamins, corticosteroids, tanning agents, hormones, retinoids, and topical cardiovascular agents. 
     
     
       9. The composition of  claim 8 , wherein said cosmetic, pharmaceutical, or other topical agent is selected from the group consisting of clotrimazole, ketoconazole, miconazole, griseofulvin, econazole, metronidazole, hydroxyzine, diphenhydramine, pramoxine, lidocaine, procaine, mepivacaine, monobenzone, erythromycin, tetracycline, clindamycin, meclocycline, hydroquinone, hydroquinone monoether, minocycline, naproxen, ibuprofen, theophylline, cromolyn, albuterol, retinol, retinyl acetate, retinyl palmitate, retinoic acid, 13-cis retinoic acid, hydrocortisone, hydrocortisone 21-acetate, hydrocortisone 17-valerate, hydrocortisone 17-butyrate, betamethasone valerate, betamethasone dipropionate, triamcinolone acetonide, fluocinonide, clobetasol propionate, benzoyl peroxide, crotamiton, propranolol, promethazine, salicylic acid, vitamin E and vitamin E acetate. 
     
     
       10. A composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) at least 1% by total weight of the composition of at least one compound selected from the group consisting of N-acetyl aldosamines, N-acetylamino acids, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof,
 wherein said N-acetyl aldosamine has the formula: 
 
       
         
           
           
               
               
           
         
       
       wherein n is an integer; R 1  is selected from the group consisting of CHO, CONH 2 , and COOR 3 ; R 2  is selected from the group consisting of H, I, F, Cl, Br, and an alkyl, alkoxyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form having 1 to 19 carbon atoms; R 3  is selected from the group consisting of H and an alkyl, aralkyl, or aryl group having from 1 to 9 carbon atoms,
 wherein said N-acetylamino acid or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycine, N-acetyl-alanine, N-acetyl-valine, N-acetyl-leucine, N-acetyl-isoleucine, N-acetyl-serine, N-acetyl-threonine, N-acetyl-tyrosine, N-acetyl-cysteine, N-acetyl-methionine, N-acetyl-aspartic acid, N-acetyl-asparagine, N-acetyl-glutamine, N-acetyl-arginine, N-acetyl-lysine, N-acetyl-histidine, N-acetyl-phenylalanine, N-acetyl-tyrosine, N-acetyl-tryptophan, N-acetyl-proline, N-acetyl-β-alanine, N-acetyl-taurine, N-acetyl-r-aminobutanoic acid, N-acetyl-hydroxyproline, N-acetyl-canavanine, N-acetyl-hydroxylysine, N-acetyl-cycloserine, N-acetyl-homoarginine, N-acetyl-norleucine, N-acetyl-norvaline, N-acetyl-homoserine, N-acetyl-methylserine, N-acetyl-hydroxyvaline, N-acetyl-ethionine, N-acetyl-methoxinine, N-acetyl-β-aminoisobutanoic acid, N-acetyl-homocysteine, N-acetyl-cysteine sulfinic acid, N-acetyl-homophenylalanine, N-acetyl-homotryptophan, N-acetyl-5-hydroxytryptamine (N-acetylserotonin), N-acetyltryptamine, N-acetyl-ornithine, N-acetyl-citrulline, N-acetyl-argininosuccinic acid, N-acetyl-dopa, N-acetyl-3-iodotyrosine, N-acetyl-3,5-diiodotyrosine, N-acetyl-3,5,3′-triiodothyronine, N-acetyl-thyroxine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-cystine, N-acetyl-homocystine, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof, and N-acetyl glutamic acid and isomeric or nonisomeric, free acid, lactone, amide, or ester forms thereof. 
 
     
     
       11. A composition comprising:
 (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders,   (B) at least 1% by total weight of the composition of at least one compound selected from the group consisting of N-acetyl aldosamines, N-acetylamino acids, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof,
 wherein said N-acetyl aldosamine has the formula: 
   
       
         
           
           
               
               
           
         
       
       wherein n is an integer; R 1  is selected from the group consisting of CHO, CONH 2 , and COOR 3 ; R 2  is selected from the group consisting of H, I, F, Cl, Br, and an alkyl, alkoxyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form having 1 to 19 carbon atoms; R 3  is selected from the group consisting of H and an alkyl, aralkyl, or aryl group having from 1 to 9 carbon atoms, 
       wherein said N-acetylamino acid is N-acetyl-proline or has the formula: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is H or an alkyl or aralkyl group having 1 to 14 carbon atoms; n is an integer; R 2  is OH, NH 2  or OR 3 ; and R 3  is an alkyl, aralkyl or aryl group having 1 to 9 carbon atoms which may be saturated or unsaturated, straight or branched chain or cyclic form; H attached to a carbon atom may be substituted by I, F, Cl, Br or an alkoxyl group having 1 to 9 carbons; and R 1  may carry OH, SH, SCH 3 , COOH, NH 2 , CONH 2 , guanidine or heterocyclic group, 
       and wherein said N-acetylamino acid is not N-acetylcysteine or a derivative thereof, and
 (C) a cosmetic, pharmaceutical or other topical agent. 
 
     
     
       12. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of a composition comprising at least one compound selected from the group consisting of N-acetyl aldosamines, N-acetylamino acids and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof,
 wherein said N-acetyl aldosamine has the formula:   
       
         
           
           
               
               
           
         
       
       wherein n is an integer; R 1  is selected from the group consisting of CHO, CONH 2 , and COOR 3 ; R 2  is selected from the group consisting of H, I, F, Cl, Br, and an alkyl, alkoxyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form having 1 to 19 carbon atoms; R 3  is selected from the group consisting of H and an alkyl, aralkyl or aryl group having from 1 to 9 carbon atoms, and
 wherein said N-acetylamino acid or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycine, N-acetyl-alanine, N-acetyl-valine, N-acetyl-leucine, N-acetyl-isoleucine, N-acetyl-serine, N-acetyl-threonine, N-acetyl-tyrosine, N-acetyl-cysteine, N-acetyl-methionine, N-acetyl-aspartic acid, N-acetyl-asparagine, N-acetyl-glutamine, N-acetyl-arginine, N-acetyl-lysine, N-acetyl-histidine, N-acetyl-phenylalanine, N-acetyl-tyrosine, N-acetyl-tryptophan, N-acetyl-proline, N-acetyl-β-alanine, N-acetyl-taurine, N-acetyl-r-aminobutanoic acid, N-acetyl-hydroxyproline, N-acetyl-canavanine, N-acetyl-hydroxylysine, N-acetyl-cycloserine, N-acetyl-homoarginine, N-acetyl-norleucine, N-acetyl-norvaline, N-acetyl-homoserine, N-acetyl-methylserine, N-acetyl-hydroxyvaline, N-acetyl-ethionine, N-acetyl-methoxinine, N-acetyl-β-aminoisobutanoic acid, N-acetyl-homocysteine, N-acetyl-cysteine sulfinic acid, N-acetyl-homophenylalanine, N-acetyl-homotryptophan, N-acetyl-5-hydroxytryptamine (N-acetylserotonin), N-acetyltryptamine, N-acetyl-ornithine, N-acetyl-citrulline, N-acetyl-argininosuccinic acid, N-acetyl-dopa, N-acetyl-3-iodotyrosine, N-acetyl-3,5-diiodotyrosine, N-acetyl-3,5,3′-triiodothyronine, N-acetyl-thyroxine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-cystine, N-acetyl-homocystine, and isomeric or nonisomeric, free acid, salt lactone, amide, or ester forms thereof, and N-acetyl-glutamic acid and isomeric or nonisomeric, free acid, lactone, amide, or ester forms thereof. 
 
     
     
       13. The method of  claim 12 , wherein said N-acetyl aldosamine or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycerosamine, N-acetyl-erythrosamine, N-acetyl-threosamine, N-acetyl-ribosamine, N-acetyl-arabinosamine, N-acetyl-xylosamine, N-acetyl-lyxosamine, N-acetyl-allosamine, N-acetyl-altrosamine, N-acetyl-glucosamine, N-acetyl-mannosamine, N-acetyl-gulosamine, N-acetyl-idosamine, N-acetyl-galactosamine, N-acetyl-talosamine, N-acetyl-glucoheptosamine, N-acetyl-galactoheptosamine, N-acetyl-mannoheptosamine, N-acetyllactosamine, N-acetylmuramic acid, N-acetylneuramine, N-acetylneuramin Lactose, N-acetyl-glyceraminic acid, N-acetyl-erythrosaminic acid, N-acetyl-threosaminic acid, N-acetyl-ribosaminic acid, N-acetyl-arabinosaminic acid, N-acetyl-xylosaminic acid, N-acetyl-lyxosaminic acid, N-acetyl-allosaminic acid, N-acetyl-altrosaminic acid, N-acetyl-glucosaminic acid, N-acetyl-mannosaminic acid, N-acetyl-gulosaminic acid, N-acetyl-idosaminic acid, N-acetyl-galactosaminic acid, N-acetyl-talosaminic acid, N-acetyl-heptoglucosaminic acid, N-acetyl-heptogalactosaminic acid, N-acetyl-heptomannosaminic acid, N-acetyl-N-acetylneuraminic acid, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof. 
     
     
       14. The method of  claim 12 , wherein said cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, and changes associated with aging of skin, nail and hair, conditions and disorders which include dryness or loose of skin, nail and hair, xerosis, ichthyosis, palmar hyerperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin as well as diminished levels of such components in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair lubricants and luster, dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair. 
     
     
       15. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising:
 (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders,   (B) a therapeutically effective amount of at least one compound selected from the group consisting of N-acetyl aldosamines, N-acetylamino acids, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof,
 wherein said N-acetyl aldosamine has the formula: 
   
       
         
           
           
               
               
           
         
       
       wherein n is an integer; R 1  is selected from the group consisting of CHO, CONH 2 , and COOR 3 ; R 2  is selected from the group consisting of H, I, F, Cl, Br, and an alkyl, alkoxyl, aralkyl or aryl group of saturated or unsaturated, straight or branched chain or cyclic form having 1 to 19 carbon atoms; R 2  is selected from the group consisting of H and an alkyl, aralkyl, or aryl group having from 1 to 9 carbon atoms, 
       wherein said N-acetylamino acid is N-acetyl-proline or has the formula: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is H or an alkyl or aralkyl group having 1 to 14 carbon atoms; n is an integer; R 2  is OH, NH 2  or OR 3 ; and R 3  is an alkyl, aralkyl or aryl group having 1 to 9 carbon atoms which may be saturated or unsaturated, straight or branched chain or cyclic form; H attached to a carbon atom may be substituted by I, F, Cl, Br or an alkoxyl group having 1 to 9 carbons; and R 1  may carry OH, SH, SCH 3 , COOH, NH 2 , CONH 2 , guanidine or heterocyclic group, and wherein said N-acetylamino acid is not N-acetylcysteine or a derivative thereof, and
 (C) a cosmetic, pharmaceutical or other topical agent. 
 
     
     
       16. The method of  claim 15 , wherein said N-acetyl aldosamine or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycerosamine, N-acetyl-erythrosamine, N-acetyl-threosamine, N-acetyl-ribosamine, N-acetyl-arabinosamine, N-acetyl-xylosamine, N-acetyl-lyxosamine, N-acetyl-allosamine, N-acetyl-altrosamine, N-acetyl-glucosamine, N-acetyl-mannosamine, N-acetyl-gulosamine, N-acetyl-idosamine, N-acetyl-galactosamine, N-acetyl-talosamine, N-acetyl-glucoheptosamine, N-acetyl-galactoheptosamine, N-acetyl-mannoheptosamine, N-acetyllactosamine, N-acetylmuramic acid, N-acetylneuramine, N-acetylneuramin Lactose, N-acetyl-glyceraminic acid, N-acetyl-erythrosaminic acid, N-acetyl-threosaminic acid, N-acetyl-ribosaminic acid, N-acetyl-arabinosaminic acid, N-acetyl-xylosaminic acid, N-acetyl-lyxosaminic acid, N-acetyl-allosaminic acid, N-acetyl-altrosaminic acid, N-acetyl-glucosaminic acid, N-acetyl-mannosaminic acid, N-acetyl-gulosaminic acid, N-acetyl-idosaminic acid, N-acetyl-galactosaminic acid, N-acetyl-talosaminic acid, N-acetyl-heptoglucosaminic acid, N-acetyl-heptogalactosaminic acid, N-acetyl-heptomannosaminic acid, N-acetyl-N-acetylneuraminic acid, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof. 
     
     
       17. The method of  claim 15 , wherein said N-acetylamino acid or isomeric or nonisomeric, free acid, salt, lactone, amide, or ester form thereof is at least one member selected from the group consisting of N-acetyl-glycine, N-acetyl-alanine, N-acetyl-valine, N-acetyl-leucine, N-acetyl-isoleucine, N-acetyl-serine, N-acetyl-threonine, N-acetyl-tyrosine, N-acetyl-cysteine, N-acetyl-methionine, N-acetyl-aspartic acid, N-acetyl-asparagine, N-acetyl-glutamic acid, N-acetyl-glutamine, N-acetyl-arginine, N-acetyl-lysine, N-acetyl-histidine, N-acetyl-phenylalanine, N-acetyl-tyrosine, N-acetyl-tryptophan, N-acetyl-proline, N-acetyl-β-alanine, N-acetyl-taurine, N-acetyl-r-aminobutanoic acid, N-acetyl-hydroxyproline, N-acetyl-canavanine, N-acetyl-hydroxylysine, N-acetyl-cycloserine, N-acetyl-homoarginine, N-acetyl-norleucine, N-acetyl-norvaline, N-acetyl-homoserine, N-acetyl-methylserine, N-acetyl-hydroxyvaline, N-acetyl-ethionine, N-acetyl-methoxinine, N-acetyl-β-aminoisobutanoic acid, N-acetyl-homocysteine, N-acetyl-cysteine sulfinic acid, N-acetyl-homophenylalanine, N-acetyl-homotryptophan, N-acetyl-5-hydroxytryptamine (N-acetylserotonin), N-acetyltryptamine, N-acetyl-ornithine, N-acetyl-citrulline, N-acetyl-argininosuccinic acid, N-acetyl-dopa, N-acetyl-3-iodotyrosine, N-acetyl-3,5-diiodotyrosine, N-acetyl-3,5,3′-triiodothyronine, N-acetyl-thyroxine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-cystine, N-acetyl-homocystine, and isomeric or nonisomeric, free acid, salt, lactone, amide, or ester forms thereof. 
     
     
       18. The method of  claim 15 , wherein said cosmetic conditions and dermatological disorders are selected from the groups consisting of disturbed keratinization, defective syntheses of dermal components, and changes associated with aging of skin, nail and hair, conditions and disorders which include dryness or loose of skin, nail and hair, xerosis, ichthyosis, palmar hyerperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin as well as diminished levels of such components in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair lubricants and luster, dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair. 
     
     
       19. The method of  claim 15 , wherein said cosmetic, pharmaceutical, or other topical agent is selected from the group consisting of agents that improve or eradicate age spots, keratoses and wrinkles, local analgesics and anesthetics, antiacne agents, antibacterials, antiyeast agents, antifungal agents, antiviral agents, antidandruff agents, antidermatitis agents, antihistamine agents, antipruritic agents, antiemetics, antimotion sickness agents, antiinflammatory agents, antihyperkeratolytic agents, antiperspirants, antipsoriatic agents, antiseborrheic agents, hair conditioners and hair treatment agents, antiaging and antiwrinkle agents, sunblock and sunscreen agents, skin lightening agents, depigmenting agents, vitamins, corticosteroids, tanning agents, hormones, retinoids, and topical cardiovascular agents. 
     
     
       20. The method of  claim 19 , wherein said cosmetic, pharmaceutical, or other topical agent is selected from the group consisting of clotrimazole, ketoconazole, miconazole, griseofulvin, econazole, metronidazole, hydroxyzine, diphenhydramine, pramoxine, lidocaine, procaine, mepivacaine, monobenzone, erythromycin, tetracycline, clindamycin, meclocycline, hydroquinone, hydroquinone monoether, minocycline, naproxen, ibuprofen, theophylline, cromolyn, albuterol, retinol, retinyl acetate, retinyl palmitate, retinoic acid, 13-cis retinoic acid, hydrocortisone, hydrocortisone 21-acetate, hydrocortisone 17-valerate, hydrocortisone 17-butyrate, betamethasone valerate, betamethasone dipropionate, triamcinolone acetonide, fluocinonide, clobetasol propionate, benzoyl peroxide, crotamiton, propranolol, promethazine, salicylic acid, vitamin E, and vitamin E acetate. 
     
     
       21. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetyl compound selected from the group consisting of N-acetyl-cysteine sulfinic acid, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-γ-aminobutanoic acid, N-acetyl-taurine, isomeric or nonisomeric, free acid, salt, lactone, amide, and ester forms thereof,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin, nail and hair, conditions and disorders selected from dryness of or looseness of skin, nail and hair; xerosis, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles; thinning of skin, nail plate and hair; skin thickening due to elastosis of photoaging; loss or reduction of skin, nail and hair resiliency, elasticity and recoilability; lack of skin, nail and hair resiliency, elasticity and recoilability; lack of skin, nail and hair lubricants and luster; dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair; and use of the composition to increase firmness and plumpness. 
 
     
     
       22. The method of claim 21, wherein the composition further comprises a cosmetic, pharmaceutical or other topical agent. 
     
     
       23. The method of claim 22, wherein the cosmetic, pharmaceutical or other topical agent is selected from the group consisting of agents that improve or eradicate age spots, keratoses and wrinkles, local analgesics and anesthetics, antiacne agents, antibacterials, antiyeast agents, antifungal agents, antiviral agents, antidandruff agents, antidermatitis agents, antihistamine agents, antipruritic agents, antiemetics, antimotion sickness agents, antiinflammatory agents, antihyperkeratotic agents, antiperspirants, antipsoriatic agents, antiseborrheic agents, hair conditioners and hair treatment agents, antiaging and antiwrinkle agents, sunblock and sunscreen agents, skin lightening agents, depigmenting agents, vitamins, corticosteroids, tanning agents, hormones, retinoids, and topical cardiovascular agents. 
     
     
       24. The method of claim 23, wherein the cosmetic, pharmaceutical or other topical agent is selected from the group consisting of clotrimazole, ketoconazole, miconazole, griseofulvin, econazole, metronidazole, hydroxyzine, diphenhydramine, pramoxine, lidocaine, procaine, mepivacaine, monobenzone, erythromycin, tetracycline, clindamycin, meclocycline, hydroquinone, hydroquinone monoether, minocycline, naproxen, ibuprofen, theophylline, cromolyn, albuterol, retinol, retinyl acetate, retinyl palmitate, retinoic acid, 13-cis retinoic acid, hydrocortisone, hydrocortisone 21-acetate, hydrocortisone 17-valerate, hydrocortisone 17-butyrate, betamethasone valerate, betamethasone dipropionate, triamcinolone acetonide, fluocinonide, clobetasol propionate, benzoyl peroxide, crotamiton, propranolol, promethazine and salicylic acid. 
     
     
       25. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetylamino acid selected from the group consisting of N-acetyl-proline and N-acetyl-hydroxyproline as amide, ester, isomeric or nonisomeric forms thereof,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin, nail and hair, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans, and elastin, diminished levels of collagen, glycosaminoglycans, proteoglycans, and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate, and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail, and hair resiliency, elasticity and recoilability, lack of skin, nail, and hair lubricants and luster, dull and older-looking skin, nails, and hair, and fragility and splitting of nails and hair; and use of the composition to increase firmness and plumpness.   
     
     
       26. The method of claim 25, wherein the N-acetyl-proline ester is selected from the group consisting of N-acetyl-proline methyl ester, N-acetyl-proline ethyl ester, N-acetyl-proline propyl ester, N-acetyl-proline isopropyl ester, N-acetyl-proline butyl ester, N-acetyl-proline amyl ester, N-acetyl-proline hexyl ester and N-acetyl-proline octyl ester. 
     
     
       27. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetylamino acid selected from the group consisting of N-acetyl-proline and N-acetyl-hydroxyproline as amide, ester, isomeric or nonisomeric forms thereof, and a cosmetic, pharmaceutical, or other topical agents,
 wherein the cosmetic, pharmaceutical, or other topical agent is selected from the group consisting of agents that improve or eradicate age spots, keratoses and wrinkles, local analgesics and anesthetics, antiacne agents, antibacterials, antiyeast agents, antifungal agents, antiviral agents, antidandruff agents, antidermatitis agents, antihistamine agents, antipruritic agents, antiemetics, antimotion sickness agents, antiinflammatory agents, antihyperkeratotic agents, antiperspirants, antipsoriatic agents, antiseborrheic agents, hair conditioners and hair treatment agents, antiaging and antiwrinkle agents, sunblock and sunscreen agents, skin lightening agents, depigmenting agents, vitamins, corticosteroids, tanning agents, hormones, retinoids, and topical cardiovascular agents.   
     
     
       28. The method of claim 27, wherein the cosmetic, pharmaceutical or other topical agent is selected from the group consisting of clotrimazole, ketoconazole, miconazole, griseofulvin, econazole, metronidazole, hydroxyzine, diphenhydramine, pramoxine, lidocaine, procaine, mepivacaine, monobenzone, erythromycin, tetracycline, clindamycin, meclocycline, hydroquinone, hydroquinone monoether, minocycline, naproxen, ibuprofen, theophylline, cromolyn, albuterol, retinol, retinyl acetate, retinyl palmitate, retinoic acid, 13-cis retinoic acid, hydrocortisone, hydrocortisone 21-acetate, hydrocortisone 17-valerate, hydrocortisone 17-butyrate, betamethasone valerate, betamethasone dipropionate, triamcinolone acetonide, fluocinonide, clobetasol propionate, benzoyl peroxide, crotamiton, propranolol, promethazine, salicylic acid, vitamin E and vitamin E acetate. 
     
     
       29. The method of claim 27, wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of eczema, psoriasis and pruritus; and use of the composition to increase firmness and plumpness. 
     
     
       30. The method of claim 27, wherein the N-acetyl-proline ester is selected from the group consisting of N-acetyl-proline methyl ester, N-acetyl-proline ethyl ester, N-acetyl-proline propyl ester, N-acetyl-proline isopropyl ester, N-acetyl-proline butyl ester, N-acetyl-proline amyl ester, N-acetyl-proline hexyl ester and N-acetyl-proline octyl ester. 
     
     
       31. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetyl-asparagine ester selected from the group consisting of N-acetyl-asparagine methyl ester, N-acetyl-asparagine ethyl ester, N-acetyl-asparagine propyl ester, N-acetyl-asparagine isopropyl ester, N-acetyl-asparagine butyl ester, N-acetyl-asparagine amyl ester, N-acetyl-asparagine hexyl ester and N-acetyl-asparagine octyl ester,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin, nail and hair, conditions and disorders selected from looseness of skin, nail and hair, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or dimished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of such collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair lubricants and luster, dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair.   
     
     
       32. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetyl-glutamine ester selected from the group consisting of N-acetyl-glutamine methyl ester, N-acetyl-glutamine ethyl ester, N-acetyl-glutamine propyl ester, N-acetyl-glutamine isopropyl ester, N-acetyl-glutamine butyl ester, N-acetyl-glutamine amyl ester, N-acetyl-glutamine hexyl ester and N-acetyl-glutamine octyl ester,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin, nail and hair, conditions and disorders selected from looseness of skin, nail and hair, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or dimished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of such collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin, nail plate and hair, skin thickening due to elastosis of photoaging, loss or reduction of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair resiliency, elasticity and recoilability, lack of skin, nail and hair lubricants and luster, dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair.   
     
     
       33. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetylamino acid selected from the group consisting of N-acetyl-aspartic acid and N-acetyl-glutamic acid, isomeric or nonisomeric, free acid, lactone, amide, and ester forms thereof,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin and nail, conditions and disorders selected from looseness of skin and nail, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin and nail, dandruff, Darier's disease, lichen simplex chronicus, keratoses, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or dimished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of such collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin and nail plate, skin thickening due to elastosis of photoaging, loss or reduction of skin and nail resiliency, elasticity and recoilability, lack of skin and nail resiliency, elasticity and recoilability, lack of skin and nail lubricants and luster, dull and older-looking skin and nails, and fragility and splitting of nails; and use of the composition to increase firmness and plumpness.   
     
     
       34. The method of claim 33, wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of ichthyosis, eczema, psoriasis, pruritus, age spots, lentigines, melasmas, blemished skin, hyperpigmented skin and thinning of skin; and use of the composition to increase firmness and plumpness. 
     
     
       35. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-aspartic acid ester selected from the group consisting of N-acetyl-aspartic acid dimethyl ester, N-acetyl-aspartic acid diethyl ester, N-acetyl-aspartic acid dipropyl ester, N-acetyl-aspartic acid diisopropyl ester, N-acetyl-aspartic acid dibutyl ester, N-acetyl-aspartic acid diamyl ester, N-acetyl-aspartic acid dihexyl ester and N-acetyl-aspartic acid dioctyl ester,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin and nail, conditions and disorders selected from looseness of skin and nail, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin and nail, dandruff, Darier's disease, lichen simplex chronicus, keratoses, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or dimished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of such collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin and nail plate, skin thickening due to elastosis of photoaging, loss or reduction of skin and nail resiliency, elasticity and recoilability, lack of skin and nail resiliency, elasticity and recoilability, lack of skin and nail lubricants and luster, dull and older-looking skin and nails, and fragility and splitting of nails; and use of the composition to increase firmness and plumpness.   
     
     
       36. A method for treating cosmetic conditions and dermatological disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetyl-glutamic acid ester selected from the group consisting of N-acetyl-glutamic acid dimethyl ester, N-acetyl-glutamic acid diethyl ester, N-acetyl-glutamic acid dipropyl ester, N-acetyl-glutamic acid diisopropyl ester, N-acetyl-glutamic acid dibutyl ester, N-acetyl-glutamic acid diamyl ester, N-acetyl-glutamic acid dihexyl ester and N-acetyl-glutamic acid dioctyl ester,
 wherein the cosmetic conditions and dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin and nail, conditions and disorders selected from looseness of skin and nail, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin and nail, dandruff, Darier's disease, lichen simplex chronicus, keratoses, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or dimished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of such collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles, thinning of skin and nail plate, skin thickening due to elastosis of photoaging, loss or reduction of skin and nail resiliency, elasticity and recoilability, lack of skin and nail resiliency, elasticity and recoilability, lack of skin and nail lubricants and luster, dull and older-looking skin and nails, and fragility and splitting of nails; and use of the composition to increase firmness and plumpness.   
     
     
       37. The method of claim 33, wherein the composition further comprises a cosmetic, pharmaceutical or other topical agent. 
     
     
       38. The method of claim 37, wherein the cosmetic, pharmaceutical or other topical agent is selected from the group consisting of agents that improve or eradicate age spots, keratoses and wrinkles, local analgesics and anesthetics, antibacterials, antiyeast agents, antifungal agents, antiviral agents, antidermatitis agents, antihistamine agents, antipruritic agents, antiemetics, antimotion sickness agents, antiinflammatory agents, antihyperkeratotic agents, antiperspirants, antipsoriatic agents, antiseborrheic agents, antiaging and antiwrinkle agents, sunblock and sunscreen agents, skin lightening agents, depigmenting agents, vitamins, corticosteroids, tanning agents, hormones, retinoids, and topical cardiovascular agents. 
     
     
       39. The method of claim 38, wherein the cosmetic, pharmaceutical or other topical agent is selected from the group consisting of clotrimazole, ketoconazole, miconazole, griseofulvin, econazole, metronidazole, hydroxyzine, diphenhydramine, pramoxine, lidocaine, procaine, mepivacaine, monobenzone, erythromycin, tetracycline, clindamycin, meclocycline, hydroquinone, hydroquinone monoether, minocycline, naproxen, ibuprofen, theophylline, cromolyn, albuterol, retinol, retinyl acetate, retinyl palmitate, retinoic acid, 13-cis retinoic acid, hydrocortisone, hydrocortisone 21-acetate, hydrocortisone 17-valerate, hydrocortisone 17-butyrate, betamethasone valerate, betamethasone dipropionate, triamcinolone acetonide, fluocinonide, clobetasol propionate, benzoyl peroxide, crotamiton, propranolol, promethazine, salicylic acid, vitamin E and vitamin E acetate. 
     
     
       40. A composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetyl compound selected from the group consisting of N-acetyl-taurine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-Dopa, isomeric or nonisomeric, free acid, salt, lactone, amide, and ester forms thereof. 
     
     
       41. The composition of claim 40, wherein the N-acetyl-Dopa ester is selected from the group consisting of N-acetyl-Dopa methyl ester, N-acetyl-Dopa ethyl ester, N-acetyl-Dopa propyl ester, N-acetyl-Dopa isopropyl ester, N-acetyl-Dopa butyl ester, N-acetyl-Dopa amyl ester, N-acetyl-Dopa hexyl ester and N-acetyl-Dopa octyl ester. 
     
     
       42. The composition of claim 40, wherein the N-acetyl-Dopa ester is N-acetyl-3,4-O,O′-diacyl Dopa or N-acetyl-3,4-O,O′-diacyl Dopa ester. 
     
     
       43. The composition of claim 42, wherein the N-acetyl-3,4-O,O′-diacyl-Dopa ester is selected from the group consisting of N-acetyl-3,4-O,O′-diacetyl-Dopa methyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa ethyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa propyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa isopropyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa butyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa amyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa hexyl ester and N-acetyl-3,4-O,O′-diacetyl-Dopa octyl ester. 
     
     
       44. The composition of claim 42, wherein the N-acetyl-3,4-O,O′-diacyl-Dopa ester is selected from the group consisting of N-acetyl-3,4-O,O′-dipropanoyl-Dopa methyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa ethyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa propyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa isopropyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa butyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa amyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa hexyl ester and N-acetyl-3,4-O,O′-dipropanoyl-Dopa octyl ester. 
     
     
       45. The composition of claim 40, wherein the cosmetic conditions or dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin, nail and hair, conditions and disorders selected from dryness of or looseness of skin, nail and hair; xerosis, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses, acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles; thinning of skin, nail plate and hair; skin thickening due to elastosis of photoaging; loss or reduction of skin, nail and hair resiliency, elasticity and recoilability; lack of skin, nail and hair resiliency, elasticity and recoilability; lack of skin, nail and hair lubricants and luster; dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair; and use of the composition for skin lightening or increasing skin firmness and plumpness. 
     
     
       46. A method for topical treatment of cosmetic conditions or dermatoloical disorders comprising topically applying a composition comprising (A) a pharmaceutically acceptable vehicle for topical treatment of cosmetic conditions or dermatological disorders and (B) a therapeutically effective amount of at least one N-acetyl compound selected from the group consisting of N-acetyl-taurine, N-acetyl-creatine, N-acetyl-creatinine, N-acetyl-Dopa, isomeric or nonisomeric, free acid, salt, lactone, amide, and ester forms thereof. 
     
     
       47. The method of claim 46, wherein the cosmetic conditions or dermatological disorders are selected from the group consisting of disturbed keratinization, defective syntheses of dermal components, changes associated with aging of skin, nail and hair, conditions and disorders selected from dryness of or looseness of skin, nail and hair; xerosis, ichthyosis, palmar hyperkeratoses, plantar hyperkeratoses, uneven and rough surfaces of skin, nail and hair, dandruff, Darier's disease, lichen simplex chronicus, keratoses; acne, pseudofolliculitis barbae, eczema, psoriasis, pruritus, warts, herpes, age spots, lentigines, melasmas, blemished skin, hyperkeratoses, hyperpigmented skin, abnormal or diminished syntheses of collagen, glycosaminoglycans, proteoglycans and elastin, diminished levels of collagen, glycosaminoglycans, proteoglycans and elastin in the dermis, stretch marks, skin lines, fine lines, wrinkles; thinning of skin, nail plate and hair; skin thickening due to elastosis of photoaging; loss or reduction of skin, nail and hair resiliency, elasticity and recoilability; lack of skin, nail and hair resiliency, elasticity and recoilability; lack of skin, nail and hair lubricants and luster; dull and older-looking skin, nails and hair, and fragility and splitting of nails and hair; and use of the composition for skin lightening or increasing skin firmness and plumpness. 
     
     
       48. The method of claim 46, wherein the N-acetyl-Dopa ester is selected from the group consisting of N-acetyl-Dopa methyl ester, N-acetyl-Dopa ethyl ester, N-acetyl-Dopa propyl ester, N-acetyl-Dopa isopropyl ester, N-acetyl-Dopa butyl ester, N-acetyl-Dopa amyl ester, N-acetyl-Dopa hexyl ester and N-acetyl-Dopa octyl ester. 
     
     
       49. The method of claim 46, wherein the N-acetyl-Dopa ester is N-acetyl-3,4-O,O′-diacyl Dopa or N-acetyl-3,4-O,O′-diacyl Dopa ester. 
     
     
       50. The method of claim 49, wherein the N-acetyl-3,4-O,O′-diacyl-Dopa ester is selected from the group consisting of N-acetyl-3,4-O,O′-diacetyl-Dopa methyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa ethyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa propyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa isopropyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa butyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa amyl ester, N-acetyl-3,4-O,O′-diacetyl-Dopa hexyl ester and N-acetyl-3,4-O,O′-diacetyl-Dopa octyl ester. 
     
     
       51. The method of claim 49, wherein the N-acetyl-3,4-O,O′-diacyl-Dopa ester is selected from the group consisting of N-acetyl-3,4-O,O′-dipropanoyl-Dopa methyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa ethyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa propyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa isopropyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa butyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa amyl ester, N-acetyl-3,4-O,O′-dipropanoyl-Dopa hexyl ester and N-acetyl-3,4-O,O′-dipropanoyl-Dopa octyl ester.