方便合成新系列的N芳基-5-(吡啶-3-基)-1 H / 3 H 1,2,3-三唑-4腈和烷基N芳基-5-(吡啶基)据报道有3-yl)-1 H / 3 H -1,2,3-三唑-4-羧酸酯。对新合成的5-(吡啶-3-基)-1,2,3-三唑衍生物的抗菌和抗真菌活性进行了评估。这些三唑衍生物中的一些表现出中等的抗菌活性。
Enantioselective Synthesis of Multifunctionalized 4<i>H</i>-Pyrans via Formal [4 + 2] Annulation Process by Bifunctional Phosphonium Salt Catalysis
作者:Jia-Hong Wu、Jianke Pan、Juan Du、Xiaoxia Wang、Xuemei Wang、Chunhui Jiang、Tianli Wang
DOI:10.1021/acs.orglett.9b04079
日期:2020.1.17
highly enantioselective formal [4 + 2] annulation involving electron-deficient allenes as C2-synthons has been developed under bifunctional phosphonium salt catalysis. With this catalytic protocol, a wide range of synthetically interesting and highly functionalized chiral 4H-pyran derivatives were readily prepared in good yields (up to 99%) with outstanding diastereo- and enantioselectivities (up to
An efficient enantioselective [3+2] cycloaddition of isomünchnones with methyleneindolinones that are generated by an in situ intramolecular addition of the carbonyl group to rhodium carbenes is realized with a chiral N,N′-dioxide/Zn(II) complex as a Lewis acid. A series of chiral oxa-bridged 3-spiropiperidines are obtained in high yields with excellent dr and excellent ee values.
使用手性N , N '-二氧化物/Zn( II ) 络合物作为路易斯酸,通过将羰基原位分子内加成到卡宾铑上,实现了异明酮与亚甲基吲哚酮的有效对映选择性 [3+2] 环加成反应. 以高产率获得了一系列手性氧杂桥联的 3-螺哌啶,具有优异的 dr 和优异的 ee 值。
Reactions of Wittig Reagents with Episulfides or Elemental Sulfur
The reactions of Wittig reagents with episulfides gave symmetrical olefins and triphenylphosphine sulfide in moderate yields. The same olefins were obtained by reactions of Wittig reagents with elemental sulfur. These reactions might proceed through thiocarbonyl intermediates, the existence of which was confirmed by Diels–Alder reactions with dienes.
NHC-Catalyzed Aldol-Like Reactions of Allenoates with Isatins: Regiospecific Syntheses of γ-Functionalized Allenoates
作者:Sha Li、Ziwei Tang、Yang Wang、Dan Wang、Zhanlin Wang、Chenxia Yu、Tuanjie Li、Donghui Wei、Changsheng Yao
DOI:10.1021/acs.orglett.8b04082
日期:2019.3.1
carbene (NHC) catalyzed γ-specific aldol-like reaction between allenoates and isatins has been achieved under mild conditions, giving trisubstituted allene derivatives bearing isatin moiety in moderate to good yields with high diastereoselectivity and excellent atom efficiency. The DFT computations indicated that the formation of the γ-adduct was more energetically favorable than that of the α-adduct. The
the α,β-unsaturated carboxylate class was developed by which synthesis of (+)- and (−)-enantiomers of 1,2-benzothiazine-1,1-dioxide acetates has been achieved with a good yield and an excellent level of enantioselectivity. A comparative structure–activity relationship study yielded the following order of aldosereductase inhibition activity: (−)-enantiomers > racemic > (+)-enantiomers. Further, a molecular