摘要 |
<p>1396801 Peptides HOECHST AG 3 July 1972 [1 July 1971 20 Jan 1972] 30984/72 Heading C2C [Also in Division C3] Peptides are prepared by reacting protected amino acids or protected peptides of the formula in which Z is an amino protective group or pyroglutamyl, Y is C 1-6 alkyl optionally substituted by one or more substituents selected from OH, NH 2 , SH, esterified carboxy, carbamoyl guanidino, aryl, imidazolyl and indolyl, which may be suitably protected, where required, and the group -NH-CH-Y- may also be pyrrolidinyl, R is di-, tri-, tetra- or penta-chlorophenyl, nitrophenyl or chloronitrophenyl and m 1 is 0 to 10, with amino acids or peptides which may be protected and correspond to the formula in which Y and -NH-CHY are as defined above, m 2 is 0 to 500 and Q is OH, alkoxy or arylalkoxy, or an amino group optionally substituted by alkyl, aralkyl or aryl groups, or Q is a polymer support linked in ester or amide form, in the presence of compounds of the formula in which X is the group C=O, C=S or -N= and X and N are members of a 5- or 6-membered optionally substituted heterocyclic ring which may be fused to a benzene ring and/or which contains 1 or 2 further hetero atoms, and the pK-value of which when measured at 30‹ C. in a 0À5 molar solution in a mixture of 6 parts by volume of the dimethyl methyl ether of diethyleneglycol and 4 parts by volume of water is within the range 3À7 to 4À2, and, if necessary or desired, splitting off the protective groups. 1 - Hydroxy - 4,6 - dimethyl - 3,5 - dichloro - 2- pyridone is prepared by chlorinating 1-hydroxy- 4,6-dimethyl-2-pyridone. 3 - Hydroxy - 4 - methyl - 2,3 - dihydrothiazole- 2-thione is made by cyclizing 5-thioxo-6-oxa-4- thia-2-octanone oxime, obtained by reacting hydroxylamine hydrochloride with 5-thioxo-6- oxa-4-thia-2-octanone, which is prepared by reacting chloroacetone with C 2 H 5 OCSSK. Reference has been directed by the Comptroller to Specification 1,308,161.</p> |