Trichloroacetaldehyde tosylhydrazone acts as an excellent precursor of diazodithioacetate which is generated by treatment of the hydrazone with sulfide ion. This spontaneously cyclizes it to 5-mercapto-1,2,3-thiadiazole. The precursor also gives a 5-amino-1,2,3-triazole on reaction with an amine. α,α-Dichloro ketone tosylhydrazones similarly cyclize to give 1,2,3-thiadiazoles and 1,2,3-triazoles.

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A novel 15-methoxyansamitocin P-3 [2], in company with three known maytansinoids 1, 3, and 4, was isolated for the first time from two Japanese mosses, Isothecium subdiversiforme and Thamnobryum sandei. All are potent cytotoxic compounds.

Microorganisms which hydrogenate 2-nitro-l-phenyl-l-propene were screened in type cultures and soil samples. Some actinomycetes belonging to Rhodococcus, Nocardia and Mycobacterium asymmetrically reduced the substrate and gave optically active 2-nitro-l-phenylpropane. Among them, Rhodococcus rhodochrous IFO 3338 gave the best results. The saturated compoundwas obtained quantitatively, when cultivation was carried out for 3 days at 30°C with a substrate concentration of 0.4%. The optical purity of the product was seriously affected by the pH of the medium. The more acidic the medium,the higher the enantiomeric excess. The results suggested that non-enzymatic racemization of the product takes place even under neutral conditions. Other substrates, such as 2-nitro-1-propene were also converted to optically active 2-nitro-l-substituted propane.

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