天堂网亚洲,天天操天天搞,91视频高清,菠萝蜜视频在线观看入口,美女视频性感美女视频,95丝袜美女视频国产,超高清美女视频图片

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List Betulin
473-98-3

Betulin synthesis

3synthesis methods
-

Yield:473-98-3 90%

Reaction Conditions:

with lithium aluminium tetrahydride in tetrahydrofuran for 5 h;Reflux;Inert atmosphere;Sealed tube;

Steps:

4.4. Reduction of C-28 carboxylic acid group of 1, 8, and 9
General procedure: To a dried 25 mL glass vial equipped with a magnetic stirrer, containing13.7 mg (0.03 mmol) of (+)-ursolic acid (1), 2 mL of a 0.02Msolution of LiAlH4 in dried THF (0.04 mmol) were added to the vialunder argon. The vial was sealed, and the mixture was stirred withreflux for 5 h, it was cooled to room temperature. Next, the reactionmixture was diluted with aqueous ether, extracted with CH2Cl2 (DCM),dried over anhydrous Na2SO4, evaporated to dryness and chromatographedover silica gel to obtain 12.0 mg (0.027 mmol) of the product,(+)-uvaol (10), with a reaction yield of 90.9%. Following this sameprocedure, 12.0 mg (0.03 mmol) of the product (+)-erythrodiol (11,with a yield of 90.9%) were prepared from 13.7 mg (0.03 mmol) of(+)-oleanolic acid (8, purchased from Sigma), and 7.9 mg(0.018 mmol) of the product (+)-betulin (12) (with a yield of 90.0%)were prepared from 9.1 mg (0.02 mmol) of (+)-betulinic acid (9, isolatedfrom our previous study).

References:

Ren, Yulin;Anaya-Eugenio, Gerardo D.;Czarnecki, Austin A.;Ninh, Tran Ngoc;Yuan, Chunhua;Chai, Hee-Byung;Soejarto, Djaja D.;Burdette, Joanna E.;de Blanco, Esperanza J. Carcache;Kinghorn, A. Douglas [Bioorganic and Medicinal Chemistry,2018,vol. 26,# 15,p. 4452 - 4460] Location in patent:supporting information

FullText

Betulin Related Search: