4 results about "Milbemycin" patented technology

The invention relates to a synthesis method of milobalin or acid salt thereof, and belongs to the technical field of medicine synthesis. In order to solve the problem that chiral resolution needs to be adopted in the prior art, the invention provides a synthesis method of miloabalin or an acid salt thereof, which comprises the following steps: under the action of an organic strong base, carrying out Michael addition reaction on a compound shown as a formula III and acetonitrile in a non-polar organic solvent at a low temperature of-50 DEG C or below to obtain an intermediate product; under the alkaline condition, the intermediate product is subjected to an oxidation reaction and a hydrolysis reaction under the action of an oxidizing agent, after the reaction is finished, an intermediate product is obtained through acidification, and the intermediate product is subjected to a high-temperature decarboxylation reaction in an aprotic solvent to obtain a compound of a formula VI; and carrying out Hofmann degradation reaction on the compound of formula VI to obtain the compound of formula I miloabalin or miloabalin acid salt. The method has the advantages of high stereoselectivity, no need of chiral resolution operation, avoidance of the problem of large material loss caused by resolution, high chiral purity and high yield.

The invention relates to a novel 16-membered macrolide compound 13alpha-O-alpha-L-oleandrosyl-23-alpha-hydroxy-25-isopropyl milbemycin beta3, a preparation method of the novel 16-membered macrolide compound 13alpha-O-alpha-L-oleandrosyl-23-alpha-hydroxy-25-isopropyl milbemycin beta3, and an application of the novel 16-membered macrolide compound 13alpha-O-alpha-L-oleandrosyl-23-alpha-hydroxy-25-isopropyl milbemycin

The invention belongs to the field of molecular biology and enzyme engineering, and provides a transaminase mutant which can catalyze resolution of high-concentration 3-ethyl bicyclo [3.2. 0] hept-3-ene-6-ketone to obtain (1R, 5S)-3-ethyl bicyclo [3.2. 0] hept-3-ene-6-ketone (DB01). The method provided by the invention solves the problems of many ketol post-treatment steps, high cost, easy deterioration of a ketone substrate in the separation process and the like in the existing industrial synthesis route, and has a wide market prospect.

The application discloses a Paraconiothyrium cyclothyrioides PF432 and a preparation method and application of metabolites thereof. The strain is preserved in the China Center for Type Culture Collection, and the preservation number is CCTCC M 20252943. Through liquid fermentation and chromatographic separation, 32 compounds, i.e. compounds 1-21, 22-29 and 30-32, are obtained from fermentation products of ME culture medium, PD culture medium and Gao's No. 1 culture medium of the strain, and the structures are identified through NMR, MS and single crystal X-ray diffraction analysis. Active tests show that the compounds have significant inhibiting effects on Xanthomonas oryzae pv. oryzae and Xanthomonas campestris pv. oryzae, wherein the in-vivo prevention and treatment effects of compounds 10, 15 and 16 on Xanthomonas oryzae pv. oryzae at a concentration of 500 ng / mL are better than that of positive control milbemycins. The application provides new candidate compounds for green prevention and control of plant bacterial diseases.