Application of Aryl Siloxane Cross-Coupling to the Synthesis of Allocolchicinoids
摘要:
In this communication, we report a new approach to the allocolchicine carbocyclic skeleton based upon an aryl siloxane coupling reaction and a phenanthrol ring expansion. These key steps allow for the selective functionalization of every carbon within the carbocyclic framework. The siloxane coupling-phenanthrol sequence was applied to the synthesis of two allocolchicinoids, including the first fully synthetic approach to N-acetyl colchinol-O-methyl ether (NCME).
Rearrangement of a Transient Gold Vinylidene into Gold Carbenes
作者:Wouter Debrouwer、Alois Fürstner
DOI:10.1002/chem.201700326
日期:2017.3.28
metastable species evolved into the cationic gold carbene complex 22 bearing a phenanthrene unit and a hydroxyl group at the aurated center; the recorded data suggest that this product might be better viewed as an acylgold species protonated by triflic acid. The use of [Me3O⋅BF4] as the activating agent led to formation of the analogous Fischer‐type carbene 24, whereas replacement of gold by the [CpRu(PPh3)2]+
Efficient Synthesis of Dibenzo[<i>a</i>,<i>c</i>]cyclohepten-5-ones via a Sequential Suzuki−Miyaura Coupling and Aldol Condensation Reaction
作者:Young Lok Choi、Chan-Mo Yu、Bum Tae Kim、Jung-Nyoung Heo
DOI:10.1021/jo900508z
日期:2009.5.15
strategy for the synthesis of a 7-membered-ring system with a Suzuki−Miyaura coupling followed by an acid/base-promoted intramolecular aldol condensation reaction has been developed. The reaction of 2′-bromoacetophenones with 2-formylphenylboronic acids in the presence of Pd(OAc)2 and CataCXium PIntB L8 efficiently provided biaryl compounds, which were transformed to a wide array of dibenzo[a,c]cyclohepten-5-ones
Pyridyl alkane acid amides as cytostatics and immunosupressives
申请人:Klinge Pharma GmbH
公开号:US20030162972A1
公开(公告)日:2003-08-28
The invention relates to new pyridyl alkane acid amides according to general formula (I) as well as methods for their production, medicaments containing these compounds as well as their medical use, especially in the treatment of tumors or for immunosuppression.
1
Bis-periazulene (cyclohepta[def]fluorene), which is an unknown pyrene isomer, was synthesized as kinetically protected forms. Its triaryl derivatives 1c–e exhibited the superimposed electronic structures of peripheral, polarized, and open-shell π-conjugated systems. In contrast to previous theoretical predictions, bis-periazulene derivatives were in the singlet ground state. Changing an aryl group
作者:G. L. BUCHANAN、J. W. COOK、J. D. LOUDON、J. MACMILLAN
DOI:10.1038/162692a0
日期:1948.10
WHILE the methoxylated carbon-system of (IV) is conclusively established for certain degradation products of colchicine1,2, the synthesi&sgrave; of such unsymmetrically substituted dibenzcycloheptatrienes, necessary for further work, has hitherto miscarried, because of difficulties which are partly concealed and partly apparent2–4. A synthesis which promises to afford the requisite degree of adaptability