Preparation of 4,6-diaminopyrazolo[3,4-<i>d</i>] pyrimidines with variations in substitution at the 1- and 3-positions
作者:Philip L. Southwick、Balram Dhawan
DOI:10.1002/jhet.5570120621
日期:1975.12
of new derivatives of 4,6-diaminopyrazolo[3,4-d]pyrimidines substituted in the 1- and/or 3-positions have been obtained from reactions of guanidine carbonate with 1- and/or 3-substituted-5-amino-4-cyanopyrazoles. Use of triethanolamine as a reaction medium permitted preparation of certain derivatives which could not be obtained from the previously described fusion procedure. Some derivatives of 4-aminopyrazolo[3
从碳酸胍与1-和/或3-取代的-5-的反应中获得了许多在1-和/或3-位被取代的4,6-二氨基吡唑并[3,4- d ]嘧啶的新衍生物。氨基-4-氰基吡唑。使用三乙醇胺作为反应介质允许制备某些衍生物,这些衍生物不能从前述的融合方法中获得。还从甲酰胺与相同的5-氨基-4-氰基吡唑的反应中获得了在1-和/或3-位被取代的4-氨基吡唑并[3,4- d ]嘧啶的一些衍生物。筛选了新化合物的体内抗疟活性,但发现它们没有活性。
Electrolytic oxidation of ketones in a methanolic solution of sodium cyanide in the presence of catalytic amounts of potassium iodide
作者:Mitsuhiro Okimoto、Toshiro Chiba
DOI:10.1021/jo00075a010
日期:1993.11
The indirect electrolytic oxidation of ketones (1) in methanolic sodium cyanide was studied using iodide ion as a mediator. The product and the reactivity of ketone were dependent on the nature of the alkyl groups attached to the carbonyl group. Thus, 2-alkyl and 2,2-dialkyl ketones afforded the corresponding oxiranecarbonitriles 2 along with small amounts of methyl oxiranecarboximidate 3, whereas acetophenones exclusively yielded benzoylpropanedinitriles 4.
One-pot synthesis of tetrasubstituted pyrazoles—proof of regiochemistry
作者:Ulf Hanefeld、Charles W. Rees、Andrew J. P. White、David J. Williams
DOI:10.1039/p19960001545
日期:——
1-Alkyl-5-amino-3-aryl-4-cyanopyrazoles, useful intermediates for fused heterocyclic systems, are synthesised by a one-pot three-step procedure from acid chlorides, malononitrile and alkylhydrazines, The regiochemistry of the hydrazine incorporation was proved in each case by X-ray crystallography and NMR spectroscopy.