3323-73-7Relevant articles and documents
New photosensitive polymers: Synthesis and free radical polymerization of oxypyridinium and oxyisoquinolinium functionalized methacrylate and styrene derivatives
Goertz, Verena,Ritter, Helmut
, p. 4258 - 4265 (2002)
Polymerizable hydroxypyridinium and hydroxyisoquinolinium salts 1a-4a, 2d, and 3d have been prepared from vinylbenzyl chloride or glycidyl methacrylate and 3-hydroxypyridine (2), 4- or 5-hydroxyisoquinoline (1, 3), and 8-hydroxyquinoline (4). Radical homo- and copolymerization with styrene or methyl methacrylate of the salts 1a-3a, 2d, and 3d produced (co)polymers 1e, 2e, 2f, 3f, 1g, 2g, 2h, and 3h. The photosensitive dipolar oxypyridinium or oxyisochinolinium betaine structures were generated in solutions with triethylamine from the low molecular weight and polymeric salt precursors. For the model compounds 1b-4b and (co)polymers 1e, 2e, 2f, 3f, 1g, 2g, 2h, and 3h, the degradation of the longest wavelength absorption of this betaine structure was detected during UV irradiation. UV irradiation of the model compound N-benzyl-4-hydroxyisochinolinium chloride (1b) in the presence of triethylamine produced the expected aziridine type structure 1k by intramolecular cyclization.
A benidipine hydrochloride method for synthesizing intermediate
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Paragraph 0030-0031; 0034, (2018/07/30)
The invention discloses a synthetic method for a benidipine hydrochloride intermediate. The synthetic method comprises performing a nucleophilic substitution reaction on 3-hydroxypyridine and a benzyl halide under a solvent refluxing condition, so as to generate 1-benzyl-3-hydroxypyridiniumhalide; taking an alcohol as a solvent and reducing 1-benzyl-3-hydroxypyridiniumhalide to generate 1-benzyl-3-piperidinol; then performing transesterification reaction on 1-benzyl-3-piperidinol and ethyl acetoacetate under a refluxing condition by taking toluene as a solvent in the presence/absence of a catalyst, and under the condition that less than 30% of the alcohol is left, performing normal-pressure distillation until the alcohol completely finishes reaction, so as to obtain the product. The synthetic method is simple and has the three-step total yield of 80% or more, and all employed materials are industrialized products and are cheap and easily obtained, and the quality is easily controlled.
Synthesis of D/L-febrifugine and D/L-isofebrifugine
Takeuchi, Yasuo,Hattori, Mayumi,Abe, Hitoshi,Harayama, Takashi
, p. 1814 - 1818 (2007/10/03)
Racemic compounds (1 and 2) of the antimalarial agents febrifugine (D-1) and isofebrifugine (D-2) were synthesized using an unusual Claisen rearrangement of allyl enol ether 6 and the stereoselective reduction of 2- allylpiperid-3-one 8. This method is widely applicable to the synthesis of febirifugine derivatives.