Antibiotic YC 73 of Pseudomonas origin. 3. Synthesis of thioformin analogues.
In the earlier paper of this series1}, it was reported that YG 73 (I) of a Pseudomonas origin was a cupric complex of an acidic substance named thioformin (II), which could be synthesized by treating N-methylhydroxylamine with potassium dithioformate. Soon after the structure determination of II, the fact that such a simple thiohydroxamic acid derivative as II possesses significant antimicrobial activity prompted us to synthesize structural analogues of II. The analogues represented in the general formula III were readily prepared by the following methods. R\ yS )N-Cf (III) ho/ \h Method A : Direct thioformylation of N-substituted hydroxylamines with potassium dithioformate.
Antibiotic YC 73 of Pseudomonas origin. II. Structure and synthesis of thioformin and its cupric complex (YC 73).
The purification, isolation and properties of a new antibiotic, YC 73 (I) from the culture broth of a pseudomonad were reported previously15. The antibiotic was a cupric complex of a low molecular weight, acidic antibiotic named thioformin (II). As reported in the present paper, thioformin has been shown to be N-methylN-thioformylhydroxylamine. During the past decade, a substantial number of hydroxamic acid antibiotics have been found from a variety of microorganisms25. However, thioformin is the first antibiotic that should be grouped as a thiohydroxamic acid.
Catalytic removal of tert-butyldimethylsilyl (TBS) ether by PVP-I
Abstract A mild, efficient and rapid protocol the deprotection of alcoholic TBDMS ethers using PVP-1 as catalyst in methanol, the procedure of deprotection of various TBDMS ethers were found to be very convenient, easy work-up, high yielding.