Aminoboronic acid derivatives, their preparation as intermediates in syntheses.

摘要

Amino boronic acid derivs. of formula (I), their optical and/or geometric isomers and their salts are new. R3+R4 = residue of a dihydroxy cpd.; R5 = H or 1-4C alkyl. Also claimed is the use of (I) for prepn. of peptide derivs. of formula (II). R = H, 1-4C alkyl, COR', or (CH2)nCO2R''; R' = 1-4C alkyl or phenylmethyl; R'' = H or 1-4C alkyl; n = 0-2; R1 = Ph, naphth-1-yl, naphth-2-yl or cyclohexyl; R3+R4 = residue of a dihydroxy cpd. (such as butane-2,3-diol, 2,3-dimethylbutane-2,3-diol or (1 alpha ,3 alpha ,5 alpha )-2,6,6-trimethylbicyclo(3.1.1) heptane, 2,3-diol((+)- alpha -pinanediol)).