首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
A simple and efficient stereoselective total synthesis of (+)‐umuravumbolide ( 1b ) and (?)‐deacetylumuravumbolide ( 1a ) starting from commercially available pentanal is described. The synthesis involves Sharpless asymmetric epoxidation, Jacobsen's hydrolytic kinetic resolution (HKR), and the Yamaguchi oxirane opening as key steps (Scheme 2).  相似文献   

2.
An efficient and highly stereoselective synthesis of stagonolide E ( 1 ) starting from the readily available hexane‐1,6‐diol ( 8 ) was accomplished, employing MacMillan α‐hydroxylation, Horner? Wadsworth? Emmons olefination, (Z)‐selective Still? Gennari olefination, and Yamaguchi lactonization as key steps.  相似文献   

3.
A highly stereoselective approach to the total synthesis of the γ‐lactone derivative botryolide E and tetrahydropyran derivative ophiocerin C via a common polyketide precursor by means of Prins cyclization and MacMillan α‐aminoxylation sequence is described. The method can conveniently be utilized for the preparation of further related γ‐lactone and tetrahydropyran derivatives.  相似文献   

4.
A highly convergent stereoselective total synthesis of stagonolide F is described starting from commercially available 5-hexen 1-ol using asymmetric dihydroxylation, Jacobsen's hydrolytic kinetic resolution (HKR), regioselective epoxide ring opening with vinyl Grignard reaction, esterification, and ring-closing metathesis (RCM) as key steps.  相似文献   

5.
The stereoselective synthesis of key fragments 3 and 7 of elaiophylin has been accomplished from readily available epichlorohydrin as the starting material. The key reactions involved are Jacobsen's kinetic resolution, Prins cyclization, pyridinium chlorochromate‐mediated oxidative cleavage, Grignard reaction, and cross‐metathesis reaction.  相似文献   

6.
The first stereoselective synthesis of the cytotoxic polyketide (4R)‐1‐(3,5‐dihydroxyphenyl)‐4‐hydroxypentan‐2‐one ( 1 ) was achieved from readily available propylene oxide and 3,5‐dimethoxybenzyl alcohol. The synthesis involves Jacobsen's hydrolytic kinetic resolution (HKR) and Grignard reaction as key steps.  相似文献   

7.
Total syntheses of iso‐cladospolide B ( 1 ) and the 12‐membered macrolactone (6S,12R)‐6‐hydroxy‐12‐methyloxacyclododecane‐2,5‐dione ( 2 ), a non‐natural product, were achieved from a common intermediate starting from commercially available 1,9‐nonane diol.  相似文献   

8.
A simple and highly efficient stereoselective total synthesis of (11β)‐11‐methoxycurvularin ( 5 ), a polyketide natural product, was achieved. The synthesis commenced with a Cu‐mediated regioselective opening of (2S)‐2‐methyloxirane ( 6 ) and comprised a Keck asymmetric allylation and intramolecular Friedel–Crafts acylation as key steps (Scheme 2).  相似文献   

9.
An efficient stereoselective total synthesis of the bioactive 14‐membered natural macrocyclic bislactone 4‐ketoclonostachydiol is described. The strategy involves a Jacobsen's hydrolytic kinetic resolution (HKR), epoxide opening, MacMillan α‐hydroxylation, Horner? Wadsworth? Emmons olefination, a Grignard reaction, and Hoveyda? GrubbsII‐catalyzed ring‐closing metathesis (RCM) as key steps.  相似文献   

10.
The stereoselective total synthesis of a naturally occurring α‐pyrone (=2H‐pyran‐2‐one) derivative, synargentolide A ( 1 ), and of its epimer 2 (with the originally proposed structure of synargentolide A) was efficiently accomplished involving D ‐tartaric acid as the starting material and an olefin cross‐metathesis reaction as the key step.  相似文献   

11.
A simple and highly efficient stereoselective total synthesis of xestodecalactone C ( IIb ), a polyketide natural product, was achieved (Scheme 2). The synthesis involved Keck's asymmetric allylation, a iodine‐induced electrophilic cyclization, and an intramolecular FriedelCrafts acylation as key steps.  相似文献   

12.
A highly concise and stereoselective total synthesis of (5R,7S)‐kurzilactone ( 1 ) was performed by a convergent approach by means of a Jacobsen's hydrolytic kinetic resolution, a Horner? Wadsworth? Emmons reaction for the construction of the α,β‐unsaturated δ‐lactone ring system, and a highly diastereoselective Mukaiyama aldol reaction for the introduction of the formal anti‐1,3‐diol unit (Schemes 2 and 3).  相似文献   

13.
A stereoselective total synthesis of phomonol, following organocatalytic enantioselective epoxidation and intramolecular oxa‐Michael reaction as key steps, is described. The use of readily available D ‐tartaric acid as a chiral source renders this approach quite simple and attractive.  相似文献   

14.
A simple and highly efficient stereoselective total synthesis of dodoneine ( 1 ), a naturally occurring bioactive 5,6‐dihydro‐2H‐pyran‐2‐one, was achieved. The synthesis involved Keck's asymmetric allylation, iodine‐induced electrophilic cyclization, and Grubbs' catalyzed ring‐closing metathesis as key steps.  相似文献   

15.
A stereoselective total synthesis of multiplolide A ( 1 ) and of its diastereoisomer 2 was described from easily accessible starting materials (Schemes 24). The synthetic strategy involves a Jacobsen resolution, Sharpless epoxidation, Swern oxidation, Yamaguchi reaction, and ring‐closing metathesis (RCM).  相似文献   

16.
A simple and efficient synthesis of functionalized β‐chlorohydrins is described from the regio‐ and stereoselective reaction of α‐epoxyketones with AlCl3 in acetonitrile at room temperature.  相似文献   

17.
The first total synthesis of a 10-membered macrolide, stagonolide E is described from readily available 4-penten-1-ol. The synthetic strategy involves Jacobsen’s kinetic resolution, Sharpless epoxidation, Stille-Gennari, and Yamaguchi lactonization as key reactions.  相似文献   

18.
A convergent total synthesis of mangiferaelactone has been accomplished in a highly stereoselective manner from readily available D ‐mannose. The following methods like organocatalytic enantioselective epoxidation, ring‐closing metathesis, and Steglich esterification have been employed as key steps, which make this approach more attractive.  相似文献   

19.
A stereoselective total synthesis of verbalactone has been achieved starting from commercially available hexanal. The sequence involves Maruoka allylation, diastereoselective iodine‐induced electrophillic cyclization, ring opening of epoxide, and Yamaguchi macrolactonization as the key steps.  相似文献   

20.
Seven phenolic compounds, including one new compound trans‐3,4,3′,5′‐tetrahydroxy‐4′‐methylstilbene 4‐O‐β‐D‐xylopyranosyl‐(1→6)‐β‐D‐glucopyranoside ( 1 ), together with six known compounds (+)‐hinokiol ( 2 ), 6‐hydroxy‐5,7‐dimethoxycoumarin ( 3 ), caffeic acid ( 4 ), vanillic acid ( 5 ), 4‐hydroxy‐2,6‐dimethoxyphenol‐1‐O‐β‐D‐glucopyranoside ( 6 ) and 4‐allyl‐2,6‐dimethoxyphenol‐1‐O‐β‐D‐glucopyranoside ( 7 ), were isolated from the root bark of Elsholtzia bodinieri Van't. Their structures were determined on the basis of spectroscopic and chemical evidence.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号