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1.
Friedrich Bossert Horst Meyer Egbert Wehinger 《Angewandte Chemie (International ed. in English)》1981,20(9):762-769
The aryldihydropyridines first prepared by Hantzsch almost 100 years ago have recently been found to be highly effective calcium antagonists with suitable pharmacological profiles. An illustrative example is dimethyl-l,4-dihydro-2,6-dimethyl-4-(o-nitrophenyl)pyridine-3,5-dicarboxylate (Nifedipine) which is already employed therapeutically. This substance lowers the frequency of attack of angina pectoris and reduces blood pressure. The discovery of the therapeutic activity of this class of substances initiated renewed investigation of the Hantzsch condensation and the synthesis of numerous 4-aryldihydropyridines and related compounds. Qualitative and quantitative structure/activity relationships of these substances can be deduced from their biological data. 相似文献
2.
Amidrazone 1a and the tricarbonyl derivatives 2b-d reacted in boiling ethanol in the presence of 2,5-norbornadiene 5 giving the pyridine derivatives 6b-d respectively (59-72%) and in the presence of 2,3-dihydrofuran 7 yielding the lactones 10b-d (39-44%). The 2,2′-bipyridine derivatives 6e-g were similarly obtained in good yield (81-87%) from the reaction of amidrazone 1b and tricarbonyl derivatives 2b-d in the presence of 2,5-norbornadiene 5. 相似文献
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By alternating‐current electrochemical technique crystals of copper(I) π‐complex with 1‐allylpyridinium chloride of [C5H5N(C3H5)][Cu2Cl3] ( 1 ) composition have been obtained and structurally investigated. Compound 1 crystallizes in monoclinic system, space group C2/c a = 24.035(1) Å, b = 11.4870(9) Å, c = 7.8170(5) Å, β = 95.010(5)°, V = 2150.0(2) Å3 (at 100 K), Z = 8, R = 0.028, for 4836 independent reflections. In the structure 1 trigonal‐pyramidal environment of π‐coordinated copper(I) atom is formed by a lengthened to 1.376(2) Å C=C bond of allyl group and by three chlorine atoms. Other two copper atoms are tetrahedrally surrounded by chlorine atoms only. The coordination polyhedra are combined into an original infinite (Cu4Cl62—)n fragment. Structural comparison of 1 and the recently studied copper(I) chloride π‐complexes with 3‐amino‐, 2‐amino‐, 4‐amino‐1‐allylpyridinium chlorides of respective [LCu2Cl3] ( 2 ), [L2Cu2Cl4] ( 3 ), and [LCuCl2] ( 4 ) compositions allowed us to reveal the trend of the inorganic fragment complication which depends on pKa (base) value of the corresponding initial heterocycle. 相似文献
4.
Yuan Zhang Han Luo Qixing Lu Qiaoyu An You Li Shanshan Li Zongyuan Tang Baosheng Li 《中国化学快报》2021,32(1):393-396
We studied the cascade nucleophilic addition reactions of 1,2,3-triazines with activated acetonitriles or ketones,which were used to construct highly substituted pyridines that are not easily accessed by conventional methods.The strategy addressed some structural diversity issues currently facing medicinal chemistry,and the resulting pyridines could be used as convenient precursors for the synthesis of related pharmaceuticals.In particular,our method was applied to the syntheses of the marketed drug etoricoxib and several biologically important molecules in a few steps. 相似文献
5.
Tohru TakeiTakumi Ohki Yosuke HaradaNaoto Kumagai Hiroki FukumotoTake-aki Koizumi Akihiro MaedaTakahiro Kojima Yoshihisa SeiKohei Shiramizu Masahiro AbeMasashi Oota Takakazu Yamamoto 《Tetrahedron letters》2012,53(44):5907-5910
Dibromopyridines or dibromopyridone with -(CH2)m-SO3Na group(s) has been prepared via the reactions of the corresponding dibromopyridines with -OH and -NH2 groups with sultone. These compounds were converted into polymers with the -(CH2)m-SO3H groups via organometallic polycondensation. The polymer showed proton conducting properties and high stability toward oxidation. 相似文献
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Anna A. Kończyk Joanna Szawkało Jan K. Maurin Zbigniew Czarnocki 《Helvetica chimica acta》2013,96(7):1348-1354
The highly functionalized tetrahydropyridine 4 was obtained in an indium(III) chloride catalyzed multi‐component reaction from benzaldehyde, 4‐methoxyaniline, and ethyl acetoacetate (=ethyl 3‐oxobutanoate) in the presence of [1,1′‐binaphthalene]‐2,2′‐diol (binol). It was found that binol played a beneficial role in this reaction, allowing a substantial decrease of the amount of indium salt. Also, simple organic Brønsted acids may serve as effective organocatalysts in this process. 相似文献
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The chemoselectivity of hydrodechlorination in 2-chloropyridine derivatives possessing reduction-sensitive functionalities is examined. The reaction conditions employed tolerate a variety of functionalities illustrating highly chemoselective hydrodechlorination in the presence of nitrile, allyl, terminal olefin, and nitroamine functionalities in excellent yield. Chemoselective deprotection of carboxybenzyl ethers is illustrated in moderate yield. 相似文献
10.
Chiral and achiral bipyridines are readily accessible via a solvent-free Michael addition involving solid NaOH, followed by treatment with ammonium acetate in acetic acid, as a ‘one pot’ more benign protocol, affording pure products in high yield, typically >80%. 相似文献