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
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
Hypervalent iodine(<scp>iii</scp>) induced oxidative olefination of benzylamines using Wittig reagents
作者:Vijayalakshmi Ramavath、Bapurao D. Rupanawar、Satish G. More、Ajay H. Bansode、Gurunath Suryavanshi
DOI:10.1039/d1nj01170g
日期:——
and secondary benzylamines using 2C-Wittig reagents, which provides easyaccess to α,β-unsaturated esters. Mild reaction conditions, good to excellent yields with high (E) selectivity, and a broad substrate scope are the key features of this reaction. We have successfully carried out the gram-scale synthesis of α,β-unsaturated esters.