一种新的和立体的策略被显影,以合成相应的模板9,得到的C-6同系物1-deoxyazasugars如1-脱氧d -galactohomonojirimycin(5),1-脱氧-4-羟甲基- d -glucohomonojirimycin(6) ,及其对映体。模板9还用于获得中性的非碱性伪乙内酰胺(8),C-4氨基和1-脱氧-homoojirimycin的甲基类似物,作为1-脱氧高纯糖的新类似物。发现化合物5是α-半乳糖苷酶的有效和特异性抑制剂(K i = 1.7μM)。类似的化合物6(Ki = 28μM), ent - 5( K i = 129μM)和ent - 6( K i = 12μM)表现出对β-葡萄糖苷酶的特异性抑制作用。
Lithiation of N-boc-2-methyltetrahydro-1,3-oxazine: a synthetic equivalent for 1-lithio-3-hydroxy-1-propylamine
摘要:
A alpha-metalo amine synthetic equivalent of an unactivated primary amine, 1-lithio-3-hydroxy-1-propylamine (7) is provided by the lithiation of N-Boc-2-methyltetrahydro-1,3-oxazine (8) to give 9 which on reaction with electrophiles and hydrolysis gives derivatives of 1-substituted 3-hydroxy-1-propylamines 10-24.
One-Step Stereospecific Strategy for the Construction of the Core Structure of the 5,11-Methanomorphanthridine Alkaloids in Racemic as well as in Optically Pure Form: Synthesis of (±)-Pancracine and (±)-Brunsvigine
作者:Ganesh Pandey、Ravindra Kumar、Prabal Banerjee、Vedavati G. Puranik
DOI:10.1002/ejoc.201100601
日期:2011.8
asymmetric version of the cycloaddition using a chiral dipolarophile was applied to construct the core structure 68 with 63% ee. This strategy was successfully applied to the formal synthesis of (±)-pancracine and the total synthesis of (±)-brunsvigine. An unprecedented and interesting skeletal rearrangement product 49 was observed during the attempted assembly of the E ring from 46 through Horner-Wadsworth-Emmons
复杂的五环 5,11-甲基吗啉嘧啶的独特核心结构通过非稳定偶氮甲碱叶立德 (AMY) 的分子内 [3+2] 环加成一步立体定向构建,AMY 是通过使用 Ag 对 14 进行连续双脱甲硅烷基化生成的IF 作为单电子氧化剂。在关键步骤中单一非对映异构体的形成可以通过 AMY 对偶极体的“Re”面的内切攻击产生的首选过渡态来解释。应用使用手性亲偶极体的不对称环加成形式来构建具有 63% ee 的核心结构 68。该策略成功应用于(±)-pancracine的正式合成和(±)-brunsvigine的全合成。在从 46 到 Horner-Wadsworth-Emmons 反应组装 E 环的过程中,观察到了前所未有的有趣的骨架重排产物 49。涉及氮杂环丁烷盐形成或 Grob 型碎裂的机制被提出来解释观察到的重排。
Stereospecific Route to 5,11-Methanomorphanthridine Alkaloids via Intramolecular 1,3-Dipolar Cycloaddition of Nonstabilized Azomethine Ylide: Formal Total Synthesis of (±)-Pancracine
作者:Ganesh Pandey、Prabal Banerjee、Ravindra Kumar、Vedavati G. Puranik
DOI:10.1021/ol051321o
日期:2005.8.1
The core structure of the complex pentacyclic 5,11-methanomorphanthridine alkaloids is constructed stereospecifically in one step employing an intramolecular [3 + 2]-cycloaddition of nonstabilized azomethine ylide as the key step. The strategy is demonstrated by accomplishing the formal totalsynthesis of (+/-)-pancracine. [reaction: see text]
A β-lactam-azasugar hybrid as a competitive potent galactosidase inhibitor
作者:Ganesh Pandey、Shrinivas G. Dumbre、M. Islam Khan、M. Shabab、Vedavati G. Puranik
DOI:10.1016/j.tetlet.2006.09.005
日期:2006.11
A beta-lactam-azasugar hybrid (polyhydroxylated carbacephem) has been designed and synthesized as a potent glycosidase inhibitor. (c) 2006 Elsevier Ltd. All rights reserved.
Convergent Approach toward the Synthesis of the Stereoisomers of C-6 Homologues of 1-Deoxynojirimycin and Their Analogues: Evaluation as Specific Glycosidase Inhibitors
作者:Ganesh Pandey、Shrinivas G. Dumbre、M. Islam Khan、M. Shabab
DOI:10.1021/jo061455v
日期:2006.10.1
A new and stereoselective strategy is developed to synthesize an appropriate template 9 to obtain C-6 homologues of 1-deoxyazasugars such as 1-deoxy-d-galactohomonojirimycin (5), 1-deoxy-4-hydroxymethyl-d-glucohomonojirimycin (6), and their enantiomers. The template 9 is also used to obtain neutral nonbasic pseudo-glyconolactam (8), C-4 amino, and methyl analogues of 1-deoxy-homonojirimycin as new
一种新的和立体的策略被显影,以合成相应的模板9,得到的C-6同系物1-deoxyazasugars如1-脱氧d -galactohomonojirimycin(5),1-脱氧-4-羟甲基- d -glucohomonojirimycin(6) ,及其对映体。模板9还用于获得中性的非碱性伪乙内酰胺(8),C-4氨基和1-脱氧-homoojirimycin的甲基类似物,作为1-脱氧高纯糖的新类似物。发现化合物5是α-半乳糖苷酶的有效和特异性抑制剂(K i = 1.7μM)。类似的化合物6(Ki = 28μM), ent - 5( K i = 129μM)和ent - 6( K i = 12μM)表现出对β-葡萄糖苷酶的特异性抑制作用。
Lithiation of N-boc-2-methyltetrahydro-1,3-oxazine: a synthetic equivalent for 1-lithio-3-hydroxy-1-propylamine
作者:Peter Beak、Eul Kgun Yum
DOI:10.1021/jo00056a010
日期:1993.2
A alpha-metalo amine synthetic equivalent of an unactivated primary amine, 1-lithio-3-hydroxy-1-propylamine (7) is provided by the lithiation of N-Boc-2-methyltetrahydro-1,3-oxazine (8) to give 9 which on reaction with electrophiles and hydrolysis gives derivatives of 1-substituted 3-hydroxy-1-propylamines 10-24.