Inter- and Intramolecular Diels-Alder Reaction of Ethenetricarboxylate Derivatives
摘要:
Inter- and intramolecular [4+2] cycloaddition reactions of highly electron-deficient ethenetricarboxylates have been studied. Intermolecular Diels-Alder reaction of ethenetricarboxylate esters and cyclopentadiene proceeded at room temperature or -20 degrees C to give cycloadducts with 1:1.5-1.9 endo:exo ratio. Lewis acids such as EtAlCl2, Zn(OTf)(2) and Cu(OTf)(2) catalyzed reaction at room temperature or -40 degrees C gave cycloadducts with 3.1-5.4:1 endo:exo ratio. Reaction of N-benzYl- or N-allyl-2-furylmethylamine and 1,1-diethyl 2-hydrogen ethenetricarboxylate in the presence of EDCl/HOBt/Et3N at room temperature led directly to an intramolecular Diels-Alder adduct stereoselectively. The observed stereoselectivities were explained by the use of DFT calculations.
A class of compounds which suppress human T-lymphocyte proliferation is disclosed. The active compounds essentially contain at least the following structure:
本研究公开了一类可抑制人类 T 淋巴细胞增殖的化合物。这些活性化合物基本上至少包含以下结构:
US5686424A
申请人:——
公开号:US5686424A
公开(公告)日:1997-11-11
Simultaneous Dual Encoding of Three-Dimensional Structures by Light-Induced Modular Ligation
A highly efficient strategy for the simultaneous dual surface encoding of 2D and 3D microscaffolds is reported. The combination of an oligo(ethylene glycol)‐based network with two novel and readily synthesized monomers with photoreactive side chains yields two new photoresists, which can be used for the fabrication of microstructures (by two‐photon polymerization) that exhibit a dual‐photoreactive
Inter- and intramolecular [4+2] cycloaddition reactions of highly electron-deficient ethenetricarboxylates have been studied. Intermolecular Diels-Alder reaction of ethenetricarboxylate esters and cyclopentadiene proceeded at room temperature or -20 degrees C to give cycloadducts with 1:1.5-1.9 endo:exo ratio. Lewis acids such as EtAlCl2, Zn(OTf)(2) and Cu(OTf)(2) catalyzed reaction at room temperature or -40 degrees C gave cycloadducts with 3.1-5.4:1 endo:exo ratio. Reaction of N-benzYl- or N-allyl-2-furylmethylamine and 1,1-diethyl 2-hydrogen ethenetricarboxylate in the presence of EDCl/HOBt/Et3N at room temperature led directly to an intramolecular Diels-Alder adduct stereoselectively. The observed stereoselectivities were explained by the use of DFT calculations.