PURPOSE: To obtain the subject compound useful as e.g. an anthelmintic agent, antiparasitic agent in an industrially advantageous way by fermentative conversion of a specific avermectin compound by the aid of e.g. Streptomyces lavendulae in a nutrient medium containing carbon source, nitrogen source and inorganic salts.
CONSTITUTION: This compound, 14a-hydroxyavermectin of formula III, useful as an anthelminic or antiparasitic agent, is obtained by fermentative conversion of a compound of formula I (the broken line at the 22,23-position indicates a single or double bond at the 22,23-position; R1 is present only when the broken line represents a single bond and is H or OH; R2 is a 1-8C alkyl, 2-8C alkenyl or 3-8C cycloalkyl; R3 is OH or methoxy; R4 is H, OH or a group of formula II) (e.g. 13-deoxyavermectin B1a aglycone) in a nutrient medium containing carbon source, nitrogen source and inorganic salts, through incubation by the aid of Streptomyces lavendulae MA6555 (ATCC 14159) or its variant at 27°C and 85% RH for 48 h.
MAABUIN DEE SHIYURUMAN
NOERU EMU YANGU
