NEW RIBOFURANURONIC ACID DERIVATIVES, PROCESSES FOR PREPARATION THEREOF AND PHARMACEUTICAL COMPOSITIONS THEREOF

摘要

New tetrahydrofurancarboxylic acid derivatives of the formula: …… wherein… R<1> is amino or a protected amino group,… R<2> is amino or acylamino and… R<3> is carboxy or a protected carboxy group or a pharmaceutically acceptable salt thereof, and processes for their preparation, and also a pharmaceutical composition comprising, as an effective ingredient, the above compound in association with a pharmaceutically acceptable, substantially non-toxic carrier or excipient. The invention also relates to the microorganism Chrysosporium pannormu ATCC 20617 and to starting compounds of the formula, …… and their preparation.