Indole and Isatin Oximes: Synthesis, Reactions, and Biological Activity. (Review)

Data on methods for the production of isatin and indole aldoximes, ketoximes, and amidoximes and their reactions are reviewed. Individual syntheses of new heterocycles from indole and isatin oximes are discussed. The principal results from investigation of the biological activity of derivatives of the oximes are also presented.     

Reactions ofN,N-dibromo-tert-butylamine with ketoximes

Reactions of acetone, cyclohexanone, and adamantanone oximes withN,N-dibromo-tert-butylamine result in the correspondingC-bromo-diazene-N-oxides. In the case of benzophenone oxime,O, O'-(diphenylmethylene)-bis-benzophenone oxime has been obtained.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 176–177, January, 1994.     

Sulfonyldiazene-N-oxides

Sulfonyldiazene-N-oxides2 and3 were obtained by treatment of sulfamide with nitroso compounds1 in the presence of 1,3-dibromoisocyanurate (DBI) in neutral and acid media.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 681–683, April, 1994.     

The cycloaddition way to novel deoxy disaccharide analogs

A novel heterocycloaddition merges 2-thiono-3-ketolactones with carbohydrate glycals to afford materials which resemble disaccharides with an O-glycosidic linkage at the anomeric center and a thioether linking both C-2 and C-2′, thus creating a third heterocyclic ring. Upon desulfurization, these novel cycloadducts afford materials which are models for 2-deoxydisaccharides. Studies with two keto lactones and seven glycals are described.     

Synthesis of carbamoylformhydroxymoyl chlorides and study of their reactivities

Carbamoylformhydroxymoyl chlorides were synthesized by the reactions of carbamoylformamide oximes with sodium nitrite in the presence of hydrochloric acid, and their reactivities were examined.     

Neurosteroid analogues: synthesis of 6-aza-allopregnanolone

An efficient synthesis of 6-azapregnane derivatives and their biological activity is described. The nitrogen was introduced into the B ring using Beckmann rearrangement of the (E)-oxime of 6-oxo-B-nor-5α-pregnane derivatives. The required 3α-hydroxyl was produced either by solvolysis of the corresponding 3β-mesyloxy group or by the Meerwein-Ponndorf-Verley reduction of the 3-oxo group; this reduction could be carried out selectively with an unprotected 3,20-dioxo derivative. The binding of the 6-aza-steroids to the γ-aminobutyric acid receptor (GABA_A) was measured using [³⁵S]-tert-butyl-bicyclo[2.2.2]phosphorothionate (TBPS) and [³H]flunitrazepam. The only analogue to be slightly active was that lacking any oxygen function in position 3.     

Novel chemical modifications at the 4-position of chromones. Synthesis and reactivity of 4H-chromene-4-spiro-5′-isoxazolines and related compounds

Reactions of chromones with dilithiooximes proceed via nucleophilic 1,2-addition to give, on acidification, 4H-chromene-4-spiro-5′-isoxazoline derivatives in high yields. On treatment with concentrated H₂SO₄ the isoxazoline ring of this novel spiroannulated heterocyclic system opens to give α,β-unsaturated oximes, which undergo nitrosation, bromination, and the Beckmann rearrangement to the corresponding spiroisoxazolines and α,β-unsaturated amides, respectively. The latter can be obtained directly by the Beckmann rearrangement of 4H-chromene-4-spiro-5′-isoxazolines.     

1-氟代糖在化学-酶法合成糖类中的应用

化学-酶法合成糖类具有立体选择性和区域选择性, 逐渐成为糖类合成的主流. 1-氟代糖作为糖基供体应用于化学-酶法合成反应, 显示出越来越重要的作用, 综述了1-氟代糖在糖基转移酶和糖苷酶催化的糖类合成中的应用.     

二元酸茄呢醇乳糖和麦芽糖酯合成及生是活性测试研究

七个二元酸茄呢基单酯分别与溴代乙酰乳糖和溴代乙酰麦芽糖在四丁基溴化铵 催化下反应生成对应的糖酯，制得的十四个化合物均为新化合物，其结构经过了元 素分析、IR，~1H NMR和MS确证。并对六个化合物做了KB（人口腔上皮癌细胞）、 Bel-7402（人肝癌细胞）、HCT-8（人结肠癌细胞）三种癌细胞初步生理活性测试。     

Synthesis of o-carborane-C-carboxylates of certain natural terpene alcohols, sterols, phenols, and camphar oxime

Previously unreported esters 1b–20b were synthesized from natural terpene alcohols, sterols, plant phenols, and camphar oxime (1a–20a) by reaction with o-carborane-C-carboxylic acid chloride. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 434–436, September–October, 2006.