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1.
A modular synthesis of the lamellarin family of natural products has been developed that is based on the application of three iterative halogenation/cross-coupling reaction sequences. The ability to halogenate the pyrrole core in a regioselective fashion, even in the presence of highly electron-rich aryl substituents, has been established. The compatibility of Suzuki coupling conditions with free alcohols and phenols in the boronic acids has been employed to reduce the number of protection/deprotection steps. Indeed, the presence of a free phenol on boronic acid 3 has been determined to be critical for the successful final coupling in route to lamellarin G trimethyl ether, since protected versions fail to undergo coupling.  相似文献   

2.
3.
A highly stereoselective total synthesis of isocladosorpin is described. The key steps involved in this synthesis are oxa-Michael reaction, asymmetric propargylation, and Alder–Rickerts reaction.  相似文献   

4.
Total synthesis of (±) compactin 12 and its natural (+) enantiomer has been achieved via a multistep sequence originating from butadiene and p-benzoquinone.  相似文献   

5.
A simple and highly efficient stereoselective total synthesis of (+)-garvensintriol, isolated from the stem bark of Goniothalamus arvensis, is described using Sharpless kinetic resolution, MacMillan α-hydroxylation, and Horner-Wadsworth-Emmons olefination as the key steps.  相似文献   

6.
Liu B  Zhou WS 《Organic letters》2004,6(1):71-74
[reaction: see text] An asymmetric synthesis of the backbone of the core of natural peloruside A is described. Key elements include reiterative application of enantioselective allylation to establish the stereochemistry of the backbone and a double asymmetric aldol reaction to successfully couple two fragments.  相似文献   

7.
A stereoselective total synthesis of 13-membered macrocycle PF1163A, an antifungal agent, has been accomplished for the first time starting from d-xylose. This approach involves a diastereoselective allylation of lactal ether,3a reductive ring opening of tetrahydrofuran ring,3b asymmetric methylation reaction, Yamaguchi esterification, and ring closing metathesis as key steps.  相似文献   

8.
Herein we report the first stereoselective total synthesis of nicotlactone A via acid catalyzed acetonide deprotection followed by intramolecular lactonization in one pot as the key step.  相似文献   

9.
The first stereoselective total synthesis of quinine.   总被引:1,自引:0,他引:1  
The first entirely stereoselective total synthesis of (-)-quinine is reported.  相似文献   

10.
The synthesis of the styryl lactone Leiocarpin C has been achieved in a highly stereoselective manner using Jacobsen’s kinetic resolution, Sharpless asymmetric epoxidation and Sharpless asymmetric dihydroxylation as key steps. This is the first total synthesis of Leiocarpin C, and thus establishes for the first time the absolute stereochemistry of this natural product.  相似文献   

11.
The first total synthesis of triumfettamide (1) is described. The asymmetric syntheses of two highly functionalized units—α-hydroxylated C17 monounsaturated fatty acid unit (2) and C26 phytosphingosine (3) have been accomplished involving Sharpless asymmetric dihydroxylation, Sharpless kinetic resolution, regioselective epoxide opening, regioselective DIBAL-H reduction of acetal, Wittig olefination as the key steps. Finally N-acylation of phytosphingosine 3 with (2R,6Z)-2-hydroxy-6-heptadecenoic acid 2 followed by DDQ deprotection of PMB, provided target compound 1.  相似文献   

12.
The first stereoselective total synthesis of polyacetylene panaxjapyne C is described. The key reactions include regioselective opening of the epoxide and Cadiot-Chodkiewicz cross-coupling reactions. l-Ascorbic acid was used as a chiral pool material for the construction of the both terminal acetylenes.  相似文献   

13.
The stereoselective total synthesis of bio-active pectinolide H (1) is described. Midland’s asymmetric reduction, Sharpless dihydroxylation reactions are involved in generating the stereogenic centers at C-4′, C-5 and C-1′. Other key steps in the synthesis are Sonogashira cross coupling, Z-selective Still–Gennari olefination, one-pot acetonide deprotection–lactonization, and Lindlar’s reaction. This offers a distinctive strategy for the synthesis of γ-lactones.  相似文献   

14.
The first stereoselective total synthesis of trichodermone A using Baylis-Hillman and ring-closing metathesis (RCM) reactions as key steps is reported.  相似文献   

15.
The first total synthesis of Goniothalesdiol A, isolated from the stems of Goniothalamus amuyon (Annonaceae) is reported. The C2 stereocentre and C3/C4 syn diol were created by a Sharpless kinetic resolution followed by acetonide formation. The tetrahydropyran ring was formed and the C6 stereocentre was fixed by intramolecular oxy-Michael addition.  相似文献   

16.
17.
The first stereoselective total synthesis of the natural product (+)-dodoneine is described involving a Crimmins aldol reaction and a Horner-Wadsworth-Emmons olefination as the key steps.  相似文献   

18.
The first stereoselective total synthesis of seimatopolide A (1) has been achieved. The key steps are Keck allylation, Sharpless asymmetric dihydroxylation, cross-, and ring-closing metathesis reactions.  相似文献   

19.
The enantioselective synthesis of bio-active 5,6-dihydro-α-pyrone, pectinolide A, has been achieved in 10 steps in good overall yield. Of the three stereogenic centres, the C-5/C-6 vic-diol was obtained using diastereo- and enantioselective Brown hydroxyl crotylation, while the C-3′ stereocentre was created by Jacobsen hydrolytic kinetic resolution method.  相似文献   

20.
First stereoselective total synthesis of nonenolide stagonolide G involving a convergent strategy is described. The key reactions include Keck allylation and Grubbs ring closing metathesis reaction.  相似文献   

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