Biocatalytic Oxidation of 2-Methylquinoxaline to 2-Quinoxalinecarboxylic Acid
摘要:
A microbial process using the fungus Absidia repens ATCC 14849 is described for the oxidation of 2-methylquinoxaline to 2-quinoxalinecarboxylic acid. A campaign consisting of three 14000-L runs produced 20.5 kg of the acid with a 28% overall yield. The bioconversion gave a lower yield compared with a three step chemical synthesis (35%), but was carried out in one pot, and avoided safety issues with a di-N-oxide intermediate. Although successfully scaled to produce kilograms of 2-quinoxalinecarboxylic acid for synthesis of a drug candidate, the A. repens bioconversion is unsuitable for further scale-up due to low product concentration (similar to1 g/L). A second microbial process using Pseudomonas putida ATCC 33015 is also described for the oxidation of 2-methylquinoxaline. The P. putida bioconversion gave an 86% in situ yield at 8-L scale and yielded a product concentration approximately 10-fold greater than that of the A. repens bioconversion.
2-Formylquinoxaline-1,4-dioxide cyanoacetylhydrazones evidence significant anticoccidial properties, enhance the feed conversion and stimulate the growth of farm animals. The described compositions are non-toxic and are suitable as veterinary medicaments and feed additives for such animals.
We report the synthesis, anti‐inflammatory, and antioxidant activities of novel quinoxaline and quinoxaline 1,4‐di‐N‐oxide derivatives. Microwave‐assisted methods have been used to optimize reaction times and to improve yields. The tested compounds presented important scavenging activities and promising in vitro inhibition of soybean lipoxygenase (LOX). Two of the best LOX inhibitors (compounds 7b and 8f) were evaluated as in vivo anti‐inflammatory agents using the carrageenin‐induced edema model. One of them (compound 7b) showed important in vivo anti‐inflammatory effect (41%) similar to that of indomethacin (47%) used as the reference drug.