5220-49-5Relevant articles and documents
Total synthesis of (±)-tangutorine and chiral HPLC separation of enantiomers
Putkonen, Tiina,Tolvanen, Arto,Jokela, Reija,Caccamese, Salvatore,Parrinello, Nunziatina
, p. 8589 - 8595 (2003)
The first total synthesis of racemic tangutorine, a novel indole alkaloid, was performed in 7 steps. The key reactions, dithionite reduction and acidic cyclization provided easy access with good yields to the tangutorine skeleton. Comprehensive NMR spectroscopic data of new compounds are given. Chiral HPLC separation of enantiomers is reported.
Efficient synthesis of decahydroacridine-1,8-diones and polyhydroquinolines using the step-wise method
Hosseininasab, Fatemeh Sadat,Memarian, Hamid Reza
, (2022/01/11)
Various symmetrical and unsymmetrical decahydroacridine-1,8-dione and polyhydroquinoline derivatives were synthesized via two-step cyclocondensation reactions. The advantages of this step-wise addition of reactants in comparison with other one-pot reactions are avoiding the formation of 2 or 3 undesired by-products, therefore allowing cleaner work up of reaction. The important factor of this effective cyclocondensation method is that the prepared β-enaminone component was added dropwise to the solution, in which the Knoevenagel condensation product is slowly being formed by reaction of aldehyde molecule and 1,3-dicarbonyl compounds. The results of the proposed step-wise method are compared and discussed with those obtained in the one-pot reactions.
Preparation method of 2-chloro-7, 8-dihydro-6H-quinolin-5-ketone
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Paragraph 0056-0065, (2018/07/30)
The invention relates to a preparation method of 2-chloro-7, 8-dihydro-6H-quinolin-5-ketone. 2-chloro-7, 8-dihydro-6H-quinolin-5-ketone comprises preparation components of a component as shown in thedescription, anhydrous ethanol, anhydrous ammonium acetate, anhydrous sodium carbonate, methyl acrylate, DMF, acetonitrile, phosphorus oxychloride and ethyl acetate, and by adopting the preparation method, the existing situation of g-class production is overcome, so that the technical level reaches the industry leading position. Furthermore, the optimized process enables the order batch output ofa project to reach 15 kg, the product quality is improved obviously, the product purity reaches 99.5%, single impurities are lower than 0.1%, and heavy metal, burning residues and residual solvents meet the standards of pharmacopoeia. Technically, the process is optimized, therefore the overall yield of the process is increased by 30%, and the discharge of three wastes (waste water, waste gas andwaste residues) is reduced through the recovery of the solvents.
Stable carteolol hydrochloride, preparation method thereof and eye medicine combination
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Paragraph 0120; 0123; 0135; 0144-0146; 0157; 0168; 0179, (2017/12/06)
The invention relates to stable carteolol hydrochloride, a preparation method thereof and an eye medicine combination, in particular to a method for preparing carteolol hydrochloride. The method comprises the following steps of preparing 3-amino-2-cyclohexenone, tetrahydro-2,5(1H, 6H)-quinolinone, 5-hydroxy-3,4-dihydro-2(1H)-carbostyril and 5-(2,3-epoxypropoxy)-3,4-dihydro-2(1H)-carbostyril, and then the carteolol hydrochloride is obtained. Furthermore, the invention provides the carteolol hydrochloride crude medicine obtained according to the method, the eye medicine combination prepared by using the obtained carteolol hydrochloride as the crude medicine, and applications of the obtained carteolol hydrochloride to preparation of drugs for treating or preventing glaucoma or ocular hypertension. The method has excellent pharmaceutical characteristics, for example, the obtained crude medicine and a preparation has excellent stability.