Takashi Tsuruoka

The structures of novel nucleoside antibiotics, miharamycin A and miharamycin B

Abstract Based on 13 C- and 1 H-NMR spectral analysis the structures of miharamycins A and B have been determined to be novel 9-substituted 2-aminopurine nucleoside antibiotics as shown in Fig. 3.

Studies on the biosynthesis of bialaphos (SF-1293) Part 3. Production of phosphinic acid derivatives, MP-103, MP-104 and MP-105, by a blocked mutant of Streptomyceshygroscopicus SF-1293 and their roles in the biosynthesis of bialaphos

During biosynthetic studies on bialaphos to reveal the formation mechanisms of carbon-phosphorous bonds in detail, three new metabolites containing a H-P-C bond structure were isolated from the fermentation broth of a mutant of Streptomyces hygroscopicus SF-1293. Based on the spectroscopic analysis, the structures of these compounds have been determined as shown in Fig. 1. Transformation experiments of these metabolites to bialaphos suggested that the reduction of the phosphorous atom in phosphate will take place at an early biosynthetic stage.

The structure of a novel nucleoside antibiotic, dapiramicin A

Abstract Based on 1 H- and 13 C-NMR spectral data including deuterium induced upfield shift, the structure of dapiramicin A, a novel nucleoside antibiotic has been determined as shown in Fig. 5.