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《化学学报》1975,(2)
三烯炔诺酮(17α-乙炔基-17β-羟基雌甾-4,9,11-三烯-3-酮,Ⅰ_a)具有较异炔诺酮(Ⅱ)更强的抗排卵作用,与炔雌醚(Ⅲ)合用乃是一种常用的口服避孕药。本品若在房事前后,单独服用低剂量,也具有抑制生育的作用。18-甲基三烯炔诺酮(18-甲基-17α-乙炔基-17β-羟基性甾-4,9,11-三烯-3-酮,Ⅰ_b)是一种抗着床的口服避孕药,每星期只需服用一次。此药既不抑制排卵,也不产生因每月服用22天含有炔雌醚的口服抗排卵避孕药而引起的副作用。三烯炔诺酮(Ⅰ_a)系用半合成方法合成,即以Ⅹ为原料,经Ⅺ→Ⅸ_a→Ⅶ_a→Ⅳ_a→Ⅻ_a→ⅫⅠ_a→ⅪⅤ_a而得Ⅰ_a,或不经Ⅻ_a及ⅫⅠ_a,即将Ⅳ_a经选择乙炔化而直接得ⅪⅤ_a。dl-18-甲基三烯炔诺酮(Ⅰ_b)用全合成方法合成,以Ⅷ_b为原料,采用与合成三烯炔诺酮相似的合成路线,经Ⅸ_b→Ⅶ_b→Ⅳ_b→Ⅻ_b→ⅫⅠ_b→ⅪⅤ_b而得Ⅰ_b。或不经Ⅶ_b及Ⅳ_b,即将Ⅸ_b与无水甲醇、氯化氢气体作用而直接得Ⅻ_b。 相似文献
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以间异丙基溴苯1为起始原料,通过进攻环氧乙烷及溴代两步制得溴化物3.溴化物3与Hagemann′s酯发生偶联反应,水解后生成偶联产物5.再以路易斯酸BF3·Et2O催化化合物5进行分子内环化为关键步骤得到反式稠合中间体6,最后通过与三苯基膦碘甲烷季盐发生Wittig反应及氧化,合成了(±)-19-去甲基-4(18),8,11,13-四烯-松香烷-7-酮[19-nor-abieta-4(18),8,11,13-tetraen-7-one](8). 相似文献
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Phenyltrichlorosilane was hydrolyzed both ifi. toluene and in ether from which two kinds of prepolymers were obtained with different structures, molecular weights, and molecular weight distributions. Polymers were prepared from the prepolymers in various polymerization conditions. The ladderlike, branched, and crosslinked structures formed under different polymerization conditions were characterized by means of FTIR, ~1H and ~(29)Si-NMR, and elemental analysis. Azeotropic distillation of solvents and H_2O formed during polymerization was found useful in removing H_2O from the system and high molecular weight products with perfect ladderlike structure were obtained. 相似文献
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Hyperbranched polymers have attracted much attention over the past decade because of the expectation that theirunique molecular shape, branching pattern and surface functionality may impart unusual properties. Methods forthe synthesis of hyperbranched polymers are, however, rather limited. Cyclotrimerization of alkynes to aromaticrings is a century-old reaction. Although chemists have intensively investigated cyclotrimerization of variousdiynes in the last century, their attention was mainly f… 相似文献
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嘧啶脲类化合物的合成及其除草活性 总被引:6,自引:0,他引:6
嘧啶脲类化合物的合成及其除草活性李斌林柄栋刘长令魏晓丽(化工部沈阳化工研究院沈阳110021)关键词嘧啶异氰酸酯嘧啶脲合成除草剂40年代开发的取代脲除草剂如敌草隆等已得到了广泛应用[1],但由于用药量较大,已逐渐被磺酰脲类除草剂取代。在这类磺酰脲除草... 相似文献
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New hyperbranched polyphenylenes with high molecular weights are synthesized by the copolycyclotrimerizations of 1,4-diethynylbenzene (I) with phenylacetylene (A), 1-octyne (B), and 1-dodecyne (C) catalyzed by TaCl5-Ph4Sn. The polymers are completely soluble in common solvents such as toluene, THF, chloroform, and dichloromethane. The polymers are characterized by spectroscopic methods and all of the polymers give satisfactory analysis data corresponding to their expected molecular structures. 相似文献
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