Biomimetic Synthesis of the Tetracyclic Core of Berkelic Acid
摘要:
Acid-catalyzed condensation of 2,6-dihydroxybenzoic acid 3 with ketal aldehyde 14 in methanol at 25 degrees C, followed by CH2N2 esterification, gave a 4: 1: 4: 1 mixture of diastereomers 15b-18b in 60% yield. Equilibration of this mixture with TFA in CDCI3 provided tetracycle 15b ( 83% yield) with the complete skeleton of berkelic acid. A similar condensation at 0 degrees C afforded 15b - 18b and a reduction product 19b, which was probably formed by a 1,5-hydride shift.
Selective protein tyrosine phosphatatase inhibitors
申请人:Liu Gang
公开号:US06972340B2
公开(公告)日:2005-12-06
Compounds of formula (I)
or therapeutically acceptable salts thereof, are selective protein tyrosine kinase-B (PTP1B) inhibitors. Preparation of the compounds, compositions containing the compounds, and treatment of disorders using the compounds are disclosed.
Regioselective ortho-carboxylation of phenols catalyzed by benzoic acid decarboxylases: a biocatalytic equivalent to the Kolbe–Schmitt reaction
作者:Christiane Wuensch、Johannes Gross、Georg Steinkellner、Andrzej Lyskowski、Karl Gruber、Silvia M. Glueck、Kurt Faber
DOI:10.1039/c3ra47719c
日期:——
catalyzed carboxylation of electron-rich phenol derivatives employing recombinant benzoic acid decarboxylases at the expense of bicarbonate as CO2 source is reported. In contrast to the classic Kolbe–Schmittreaction, the biocatalytic equivalent proceeded in a highly regioselective fashion exclusively at the ortho-position of the phenolic directing group in up to 80% conversion. Several enzymes were identified
Pharmaceutical compositions containing a gamma-resorcylic acid
申请人:Science Union et Cie
公开号:US04132787A1
公开(公告)日:1979-01-02
Pharmaceutical compositions containing as active principle a .gamma.-resorcylic acid derivative of the formula: ##STR1## or a physiologically tolerable salt thereof. These pharmaceutical compositions are used especially in the treatment of thromboembolic diseases and arteriosclerosis.
[EN] SELECTIVE PROTEIN TYROSINE PHOSPHATASE INHIBITORS<br/>[FR] INHIBITEURS SELECTIFS DE PROTEINE TYROSINE PHOSPHATASE
申请人:ABBOTT LAB
公开号:WO2003020688A1
公开(公告)日:2003-03-13
Compounds of formula (I) or therapeutically acceptable salts thereof, are selective protein tyrosine kinase-B (PTP1B) inhibitors. Preparation of the compounds, compositions containing the compounds, and treatment of disorders using the compounds are disclosed.