Transition-metal-free decarboxylative thiolation of stable aliphatic carboxylates
作者:Wei-Long Xing、De-Guang Liu、Ming-Chen Fu
DOI:10.1039/d1ra00063b
日期:——
transition-metal-free decarboxylative thiolation protocol is reported in which primary, secondary, tertiary (hetero)arylacetates and α-CN substitutedacetates undergo the decarboxylative thiolation smoothly, to deliver a variety of functionalized aryl alkyl sulfides in moderate to excellent yields. Aryl diselenides are also amenable substrates for construction of C–Se bonds under the simple and mild reaction
alkylating antitumor agents. In order to study the interaction of O6-benzylguanine derivatives with AGT and to obtain greater AGT depletion, we synthesized the following O6-arylmethylguanine derivatives and related compounds: O6-(4-, 3- and 2-fluorobenzyl)guanines (2, 3, 4), O6-(4-, 3- and 2-trifluoromethylbenzyl)guanines (5, 6, 7), O6-(4-, 3- and 2-pyridylmethyl)guanines (8, 9, 10), O6-(2- and 1-naphthylmethyl)guanines
Inhibition of Human <i>O</i><sup>6</sup>-Alkylguanine-DNA Alkyltransferase and Potentiation of the Cytotoxicity of Chloroethylnitrosourea by 4(6)-(Benzyloxy)-2,6(4)-diamino-5-(nitro or nitroso)pyrimidine Derivatives and Analogues
作者:Isamu Terashima、Kohfuku Kohda
DOI:10.1021/jm970363i
日期:1998.2.1
A series of 4(6)-(benzyloxy)-2,6(4)-diamino-5-(nitro or nitroso)pyrimidine derivatives and analogues of which 4(6)-benzyloxy groups were replaced with a (2-, 3-, or 4-fluorobenzyl)oxy or (2-, 3-, or 4-pyridylmethyl)oxy group, was synthesized. The abilities of these compounds to inhibit human O-6-alkylguanine DNA alkyltransferase (AGAT) in vitro and to potentiate the cytotoxicity of 1-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3-nitrosourea (ACNU) toward HeLa S3 cells were evaluated. 2,4-Diamino-6-[(2-fluorobenzyl)oxy]-5-nitropyrimidine (3) and 2,4-diamino-5-nitro-6-(2-pyridylmethoxy) (6), whose ortho positions of the 6-substituent are modified, were much weaker in terms of these abilities than the corresponding meta-or para-modified compounds. These results are consistent with those,of our previous study using a series of O-6-benzylguanine derivatives. All 5-nitrosopyrimidine derivatives examined exerted both stronger AGAT-inhibition and ACNU-enhancement abilities than the corresponding 5-nitro derivatives. Among a variety of compounds that we have examined to date, 2,4-diamino-6-[(4-fluorobenzyl)oxy]-5-nitrbsopyrimidine (10) exhibited the strongest ability to inhibit AGAT, and its magnitude was 2.5 and 50 times those of 4-(benzyloxy)-2,6-diamino-5-nitrosopyrimidine (9) and O-6-benzylguanine (1), respectively. A strong positive correlation was observed between the ability to inhibit AGAT and to potentiate the cytotoxicity of ACNU. This strongly indicates that 4(6)-(benzyloxy)pyrimidine derivatives and their analogues potentiate ACNU cytotoxicity by inhibiting AGAT activity. To characterize the reactivity of test compounds, alkyl-transfer reactions were also carried out using the biomimetic alkyl-transfer system.
KATRITZKY A. R.; BAPAT J. B.; BLADE R. J.; LEDDY B. P.; NIE P.-L.; RAMADE+, J. CHEM. SOC. PERKIN TRANS., PART 1, 1979, NO 2, 418-425
作者:KATRITZKY A. R.、 BAPAT J. B.、 BLADE R. J.、 LEDDY B. P.、 NIE P.-L.、 RAMADE+