| abstract |
NEW MATERIAL: A peptide of the formula (AA is histidine, aspartic acid, etc.; R 1 is H, alkenyl, phenyl, etc.; R 2 and R 3 are each H, alkyl, phenyl, diradical, etc.; R 4 is H, alkyl, etc.; R 5 is CO 2 R 4 , etc.; R 6 is H, CH 3 , etc.; n is 0 or 1). n EXAMPLE: (N α CarboxymethylL-histidyl)L-leucine. n USE: Therapeutic agents for viral infections, and anti-herpetic agents. n PROCESS: For example, N α t-butoxycarbonyl-N im 2,4-dinitrophenylL-histidine and L-leucine benzyl ester are reacted in the presence of a condensing agent. The product is chromatographed on silica gel and treated with trifluoroacetic acid to remove the protecting group. The α-amino group in the deblocked product is carboxymethylated with bromoacetic acid and then treated with thiophenol to remove the other protecting group, thus yielding the compound of the formula. n COPYRIGHT: (C)1991,JPO |