Synthesis of Novel Functionalized Derivatives of 5-Nitro-3,4-dihydropyrimidin-2(1<i>H</i>)-one by the Cyclocondensation of 1-Chlorobenzyl Isocyanates with <i>N</i>,<i>S</i>- and <i>N</i>,<i>N</i>-Nitroketeneacetals
作者:Mykhaylo Vovk、Volodymyr Sukach、Andriy Bol’but、Alexander Petin
DOI:10.1055/s-2007-965933
日期:2007.3
The cyclocondensation of 1-chlorobenzyl isocyanates with S,N- and N,N-nitroketeneacetals has been employed to synthesize hitherto-unknown 6-methylthio-5-nitro-3,4-dihydropyrimidin-2(1H)-ones, 8-nitro-2,3,6,7-tetrahydroimidazo[1,2-c]pyrimidin-5(1H)-ones and 9-nitro-1,2,3,4,7,8-hexahydro-6H-pyrimido[1,6-a]pyrimidin-6(1H)-ones. Substitution of the methylthio group in 6-methylthio-5-nitro-3,4-dihydropyrimidin-2(1H)-ones provided 6-amino-5-nitro-3,4-dihydropyrimidin-2(1H)-ones, which exist in tautomeric equilibrium with 4-imino-5-nitro-3,4,5,6-tetrahydropyrimidin-2(1H)-ones. The compounds obtained, if boiled in dioxane in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), eliminate the nitro groups to give substituted 4-imino-3,4-dihydropyrimidin-2(1H)-ones.
1-氯苄异氰酸酯与S,N-和N,N-硝基烯酰基的环缩合反应被用来合成迄今为止未知的6-硫甲基-5-硝基-3,4-二氢嘧啶-2(1H)-酮、8-硝基-2,3,6,7-四氢咪唑[1,2-c]嘧啶-5(1H)-酮以及9-硝基-1,2,3,4,7,8-六氢-6H-吡咯[1,6-a]嘧啶-6(1H)-酮。对6-硫甲基-5-硝基-3,4-二氢嘧啶-2(1H)-酮中硫甲基的取代生成6-氨基-5-硝基-3,4-二氢嘧啶-2(1H)-酮,该化合物与4-亚氨基-5-硝基-3,4,5,6-四氢嘧啶-2(1H)-酮存在互变异构平衡。如果将所获得的化合物在1,8-二氮双环[5.4.0]十一烯(DBU)存在下于二噁烷中加热,会消除硝基生成取代的4-亚氨基-3,4-二氢嘧啶-2(1H)-酮。