N-tert-butoxycarbonyl-N-substituted hydrazines in SNAr displacements. Synthetic pathways to N-1-substituted anthrapyrazoles, aza-anthrapyrazoles and aza-benzothiopyranoindazoles
作者:Ambrogio Oliva、Michael Ellis、L. Fiocchi、Ernesto Menta、A. Paul Krapcho
DOI:10.1002/jhet.5570370108
日期:2000.1
stituted hydrazines has been accomplished. The use of these protected hydrazines in SNAr substitutions leads to products in which the most nucleophilic nitrogen displaces the leaving group. Treatment of these compounds with trifluoroacetic acid readily removes the Boc-protecting group and the intermediates readily undergo cyclizations to yield N-1-substitutedaza-benzothiopyranoindazoles, anthrapyrazoles
的几个合成ñ -叔-protected-丁氧羰基(BOC)ñ -取代的肼已经完成。在S N Ar取代中使用这些受保护的肼会生成大多数亲核氮取代离去基团的产物。用三氟乙酸处理这些化合物容易除去Boc保护基,并且中间体容易进行环化以产生N -1-取代的氮杂-苯并硫代吡喃并吲哚,蒽并吡咯和氮杂-蒽并吡咯。在一些氮杂-蒽吡唑的合成中采用了侧链积累。
Regioselective Synthesis of 1-Alkyl- or 1-Aryl-1<i>H</i>-indazoles via Copper-Catalyzed Cyclizations of 2-Haloarylcarbonylic Compounds
作者:Dolores Viña、Esther del Olmo、José L. López-Pérez、Arturo San Feliciano
DOI:10.1021/ol062890e
日期:2007.2.1
[reaction: see text] A general method for the one-step regioselective synthesis of 1-alkyl- or 1-aryl-1H-indazoles from ortho-halogenated alkanoylphenones, benzophenones, and arylcarboxylic acids, via copper-catalyzedamination, was developed by using 0.2% mol of CuO in the presence of K(2)CO(3). The reaction involves amination followed by intramolecular dehydration. Different functionalized alkyl
Generation of pancreatic endoderm from pluripotent stem cells using small molecules
申请人:Novo Nordisk A/S
公开号:US10221392B2
公开(公告)日:2019-03-05
A method of producing pancreatic cells or pancreatic cell precursors expressing at least 5% PDX1/NKX6.1 double positive, comprising exposing definitive endoderm cells to an effective amount of one or more small molecules, to differentiate the human definitive endoderm cells into the pancreatic cells or pancreatic cell precursors. The present invention also relates to pancreatic endoderm cells produced by said methods and uses of said pancreatic endoderm cells.