Ring closure reactions of azidouracils to oxazolo- and isoxazolopyrimidines
作者:Dang Van Tinh、Wolfgang Stadlbauer
DOI:10.1002/jhet.5570330404
日期:1996.7
presence of polyphosphoric acid leads either to oxazolo[5,4-d]pyrimidine-5,7-diones 5 (by reaction with benzoic acid 2a) or to isoxazolo[3,4-d]pyrimidine-4,6-diones 7 (by reaction with aliphatic carboxylic acids 2b,c). 5-Benzoylpyrimidinetriones 12 could be shown to cyclize to isoxazolo[5,4-d]pyrimidine-4,6-diones 15 by chlorination with phosphoruspentachloride and subsequent reaction with sodium azide.
在多磷酸存在下对6-azidouracils 1的热解会生成恶唑并[5,4- d ]嘧啶-5,7-二酮5(通过与苯甲酸2a反应)或异恶唑并[3,4- d ]嘧啶-4,6-二酮7(通过与脂族羧酸2b,c反应)。通过用五氯化磷氯化并随后与叠氮化钠反应,可以显示5-苯甲酰基嘧啶三酮12环化成异恶唑并[5,4 - d ]嘧啶-4,6-二酮15。
Ring closure reactions of β-nitroso-, β-acyl-, and β-thiocarbamoyl-α,β-unsaturated sulfilimines. Synthesis of [1,2,5]oxadiazolo[3,4-d]-, isoxazolo[3,4-d]-, and isothiazolo[3,4-d]pyrimidine derivatives from uracils
作者:Nobuaki Matsumoto、Masahiko Takahashi
DOI:10.1016/s0040-4020(02)01302-9
日期:2002.12
acils were treated with S,S-diphenylsulfilimine to give N-(1,3-dialkyluracil-6-yl)-S,S-diphenylsulfilimines. The uracilylsulfilimines were nitrosated, acylated, or thiocarbamoylated to give N-(5-nitroso-, 5-acyl-, or 5-thiocarbamoyluracil-6-yl)sulfilimines, respectively. These conjugated sulfilimines were cyclized by thermolysis or photolysis to [1,2,5]oxadiazolo[3,4-d], isoxazolo[3,4-d], or isothiazolo[3
将1,3-二烷基-6-氯尿嘧啶用S,S-二苯基硫亚胺处理,得到N-(1,3-二烷基尿嘧啶-6-基)-S,S-二苯基硫亚胺。尿嘧啶亚氨基嘧啶被亚硝化,酰化或硫代氨基甲酰化,分别得到N-(5-亚硝基-,5-酰基-或5-硫代氨基甲酰基尿嘧啶-6-基)亚磺酰亚胺。通过热解或光解将这些共轭的亚硫亚胺环化为[1,2,5]恶二唑并[3,4- d ],异恶唑并[3,4- d ]或异噻唑并[3,4- d ]嘧啶衍生物。
Isoxazolo[3,4-d]pyrimidines
申请人:Takeda Chemical Industries, Ltd.
公开号:US04202975A1
公开(公告)日:1980-05-13
Isoxazolo[3,4-d]pyrimidines of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3, respectively, are hydrogen, lower alkyl, cycloalkyl, or aryl which may be substituted by halogen, are useful as antiinflammatory-analgesic drugs, and the industrially feasible production thereof is provided.
Isoxazolo[3,4-d]pyrimidines useful as antiinflammatory-analgesic agents
申请人:Takeda Chemical Industries, Ltd.
公开号:US04129654A1
公开(公告)日:1978-12-12
Isoxazolo[3,4-d]pyrimidines of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 respectively, are hydrogen, lower alkyl, cycloalkyl, or aryl which may be substituted by halogen, are useful as antiinflammatory-analgesic drugs, and the industrially feasible production thereof is provided.