Reactions of 3-carboxymethylrhodanine (1) with aldehydes (2a-u) afforded stereoselectively the 5-mono-alkylmethylidene-3-carboxymethylrhodanines (3a-u). The configuration of the 5-monoalkylmethylidene-3-carboxymethylrhodanine (3k) were examined by X-ray structure analysis and confirmed to be Z-configuration. The stereoselective reaction path was discussed. Several 5-dialkylmethylidene-3-carboxymethylrhodanines (15a-f) and alkylamino derivatives of 3-carboxymethylrhodanines (18a-o) were also prepared. These products were evaluated for aldose reductase-inhibitory potency and half of them exhibited valuable inhibitory potency.

by both INDO9 and 4-31G10 and of the UDMH radical by INDO yield planar geometries. However, STO-3G11 predicts a nonplanar hydrazine-like structure with a 6 kcal/mol barrier at the optimized planar geometry (I and Table II).

A novel peptide antibiotic, K‐582, which exhibited significant growth inhibition of Candida, viruses and ascites tumor in mice, was found in the culture medium of a strain of Metarhizium anisopliae by Kondo et al. (J. Antibiotics33, 535–542 (1980)]. K‐582 consisted of two components, designated K‐582 A and K‐582 B. Threonine, tyrosine, ornithine, and an unusual amino acid were common in both peptides, but lysine was an extra component of K‐582 A. The unusual amino acid was identified to be threo‐γ‐hydroxy‐L‐arginine (OHArg) by means of mass, nuclear magnetic resonance and infrared spectrometries of the derivatives and the related compounds. The threonine and the arginine were assigned to be L‐configuration, and the ornithine and the tyrosine to be D‐configuration in both K‐582 A and K‐582 B, and the lysine to be L‐configuration by comparison of their optical rotatory dispersion spectra with those of standard amino acids. The elucidation of primary structure revealed that they were closely related heptapeptides with the following sequence: K‐582 A:H‐Arg‐OHArg‐Orn‐Thr‐Orn‐Lys‐Tyr‐OH; K‐582 B:H‐Arg‐OHArg‐Orn‐Thr‐Orn‐OHArg‐Tyr‐OH, and had the identical sequence in terms of the configuration of their constituents, namely L‐L‐D‐L‐D‐L‐D.

Various benzo[b]furan derivatives with a carboxymethylsulfamoyl group were prepared and evaluated for aldose reductase-inhibitory potency. Most of the compounds displayed significant inhibitory activities (IC50, 10(-8)-10(-7) M). Among the test compounds, the compounds having a carboxymethylsulfamoyl group at the 3- or 4-position exhibited the greatest inhibitory potency. Structure-activity trends of the tested compounds are discussed.

No abstract