Synthesis and stereochemistry of β-aryl-β-haloacroleins: useful intermediates for the preparation of (Z ) and (E )-2-en-4-ynecarbaldehydes and for the synthesis of rubrolides
作者:Damien Prim、Alexia Fuss、Gilbert Kirsch、Artur M. S. Silva
DOI:10.1039/a900286c
日期:——
The synthesis of α-substituted β-aryl-β-haloacroleins by two different pathways is presented. The determination of their stereochemistry by NOE experiments is reported for the first time. Furthermore, we describe the preparation of 2-en-4-ynecarbaldehydes and access to rubrolide derivatives from β-aryl-β-haloacroleins.
Continuous-Flow Preparation and Use of β-Chloro Enals Using the Vilsmeier Reagent
作者:Laurent Pellegatti、Stephen L. Buchwald
DOI:10.1021/op300168z
日期:2012.8.17
The Vilsmeier reagent is used in the preparation of a wide variety of heterocycles, such as pyrazoles, via formation of β-chloroacrolein intermediates. However, use of this extremely reactive reagent on large scale requires special precautions to avoid potentially dangerous exotherms. This article describes the safe preparation at room temperature of the Vilsmeier reagent under flow conditions for
Multicomponent reaction for the first synthesis of 2,2-dialkyl- and 2-alkyl-2-aralkyl-5,6-diaryl-2H-1,3-thiazines as scaffolds for various 3,4-dihydro-2H-1,3-thiazine derivatives
2H-1,3-thiazines, prepared via a novel and efficient multicomponent reaction, can be used as scaffolds for the synthesis of diverse 3,4-dihydro-2H-1,3-thiazines.
Two alkyl-3,4-bis(4-methoxyphenyl)pyrrole-2-carboxylates proved to be potent cytotoxic agents in the murine L1210 lymphoid leukemia screen. DNA synthesis was preferentially inhibited with the major target of the agents being de novo purine biosynthesis at the regulatory enzyme sites of PRPP-amido transferase and IMP dehydrogenase. Other enzymatic activities which were suppressed by the drugs were DNA polymerase alpha, RNA polymerases, ribonucleoside reductase and dihydrofolate reductase. The d[NTP] pools, nucleoside kinase and the pyrimidine pathway were not affected by the presence of drugs. The DNA molecule itself was not the target of the agents, i.e. no alkylation of nucleotide bases, intercalation between bases or cross-linking of DNA strands occurred. The agents did cause L1210 DNA fragmentation after 24 h incubation at 100 microM.
GREIF, D.;KROPFGANS, F.;PULST, M.;WEISS. ENFELS, M., SYNTHESIS,(1989) N, C. 515-518
作者:GREIF, D.、KROPFGANS, F.、PULST, M.、WEISS. ENFELS, M.