Synthesis and biological evaluation of RON-neoglycosides as tumor cytotoxins
摘要:
Cardenolides such as digitoxin have been shown to inhibit cancer cell growth, to reduce cancer metastasis, and to induce apoptosis in tumor cells. Among the most potent digitoxin-based cytotoxins identified to date are MeON-neoglycosides generated via oxyamine neoglycosylation. Here, we report our studies of oxyamine neoglycosylation aimed at facilitating the elucidation of linkage-diversified digitoxin neoglycoside structure-activity relationships. We identified conditions suitable for the convenient synthesis of digitoxin neoglycosides and found that sugar structure, rather than RON-glycosidic linkage, exerts the strongest influence on neoglycoside yield and stereochemistry. We synthesized a library of digitoxin neoglycosides and assessed their cytotoxicity against eight human cancer cell lines. Consistent with previous findings, our data show that the structure of RON-neoglycosidic linkages influences both the potency and selectivity of digitoxin neoglycosides. (C) 2011 Elsevier Ltd. All rights reserved.
O-Methyl oximes have been employed as nucleophiles in reactions with ketenimines derived from sulfonylazides and terminal alkynes to form N-alkylidene N′-tosylacetimidamide derivatives. The optimized conditions involved the use of CuPF6 and i-Pr2NEt in MeCN at 65 °C. Both O-methyl aldoximes and ketoximes were tolerated under the optimum conditions.
The present invention relates to the inhibition of HIV integrase, and to the treatment of AIDS or ARC by administering compounds of the following formula, or a tautomer of said compound, or a pharmaceutically acceptable salt, solvate or prodrug thereof:
1
wherein R
1
, R
2
and B
1
are as defined herein.
Preparation of dihomoallylic secondary amines through samarium mediated allylation of oximes
作者:Xuesen Fan、Yongmin Zhang
DOI:10.1016/s0040-4039(02)01042-0
日期:2002.7
Allylsamarium bromide adds to oximes derived from aromatic aldehydes and methyl aryl ketones at ambient temperature to afford dihomoallylic secondaryamines in moderate to high yields.
A ruthenium-catalyzed highly regioselective cyclization of substituted N-methoxy benzimidoyl halides with alkynes in the presence of CsOAc (25 mol%) to give substituted 1-halo and 1-alkoxy substituted isoquinolines in good to excellent yields is described.
Novel One-Pot Synthesis of <i>N</i>-Alkyl Arylamines from Oxime Ethers Using Organometallic Reagents
作者:Takeaki Naito、Partha Mukhopadhyay、Okiko Miyata
DOI:10.1055/s-2007-980358
日期:2007.6
α-disubstituted secondary arylamines from oxime ethers has been developed by two separate additions of organometallicreagents. As a related arylamine construction, very efficient synthesis of N-(diallyl)methyl arylamines is achieved via domino reactions involving addition-eliminative re-arrangement-addition reactions of acyclic and cyclic oxime ethers with allylmagnesium bromide.