Patent GB-889101-A (GB)
Title: Allantoin compounds
IPC: C07D233/88
Filed: 1960-09-01
Abstract: The invention comprises salts of sulphur containing a -amino-acid compounds as hereinafter defined with allantoin or complex aluminium salts of allantoin.  The amino-acid component, which may be racemate or an optical isomer, may have the formula R-S-(CH2)n-CH(NHR1)-COOH wherein n is 1 or 2, R1 is hydrogen or an acyl radical and R is one or two methyl or ethyl groups (when R is two groups, the compounds are sulphonium salts also containing an anion such as a halide ion) or it may be cystine or cysteine or an N-acylate thereof.  The N-acylating group may be an aliphatic acyl group, such as formyl, acetyl, propionyl, butyryl, caproyl, capryl, lauroyl, myristoyl, palmitoyl, stearoyl or oleoyl, or an aromatic acyl group such as benzoyl or p-toluoyl.  Illustrative of the complex aluminium salts of allantoin which may be used are the following, X denoting the allantoin residue C4N5N4O3:-Al(OH)2X, Al2(OH)4ClX, Al2(S O3 N H)2X, AlSO4X, Al Cl2X, Al(CH3COO)2X, AlNH4SO4X2, Al(C7H5O2)2X (aluminium benzoate allantoinate), AlBr2X, AlI2X, Al (CH3 CH(OH) COO)2 X, Al (C6H4(OH)SO3)2X, AlKSO4X2, Al(C6H4(OH)COO)2X (aluminium salicylate allantoinate) and AlNaSO4X2.  The salts of the invention are prepared by contacting the selected allantoin compound with the selected amino-acid in a neutral solvent, usually water, generally at moderately elevated temperatures.  It is stated that the salts of the amino-acids with allantoin are 1 : 1-equimolar addition compounds (except the salts with cystine, which may be mono-or di-allantoin salts), while the salts of the acids with the complex aluminium salts of allantoin are probably substitution compounds in which the acid replaces one of the radicals satisfying the valancies of the aluminium atom other than the allantoin molecule.  Examples are given.  U.S.A. Specification 2,761,867 is referred to.ALSO:Pharmaceutical and cosmetic preparations comprise salts of sulphur containing a -amino-acid compounds as hereinafter defined with allantoin or complex aluminium salts of allantoin and carriers therefor.  The amino-acid component of the salt may be a racemate or an optical isomer of an acid of the formula  R-S-(CH2)n-CH(NHR1)-COOH wherein n is 1 or 2, R1 is hydrogen or an acyl radical and R is one or two methyl or ethyl groups (when R is two groups, the compounds are sulphonium salts also containing an anion such as a halide ion) or of cystine or cysteine or an N-acylate thereof. The salts of these acids with allantoin are stated to be 1 : 1-equimolar addition compounds (except the salts with cystine, which may be mono- or diallantoin salts), while the salts of the acids with the complex aluminium salts of allantoin are probably substitution compounds in which the acid replanes one of the radicals (such radicals being halogen, hydroxy, SO3NH, SO4, CH3COO, NH4SO4, benzoate, lactate, phenolsulphonate, KSO4, NaSO4 and salicylate) satisfying the valencies of the aluminium atom other than the allantoin molecule. The compositions may take the form of lotions, creams, gels, powders, compresses, or solutions.  Aqueous or alcoholic solutions may be stabilized by addition of small amounts of sodium or potassium acid phosphate salts or amines. The salts may also be combined with other active pharmaceuticals, such as aluminium acetate or magnesium sulphate, quaternary amines, hormones, vitaamins or antiperspirants. A lubricating cream containing allantoin N-acetylmethioninate, an astringent, antiseptic body lotion containing aluminium chlorhydroxy allantoinate N-acetylmethioninate and a hair conditioner containing allantoin methioninate are described.  U.S.A. Specification 2,761,867 is referred to.