- Azelnidipine impurity and preparation method thereof
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The invention belongs to the field of preparation of azelnidipine impurities, and discloses an azelnidipine impurity and a preparation method thereof. According to the method, a key intermediate of azelnidipine is taken as a raw material, organic ammonium salt and an organic aluminon reagent are subjected to ammonolysis to obtain malonyl amidine salt, the malonyl amidine salt and the key intermediate of the azelnidipine are subjected to Hantzsch condensation, and the high-purity azelnidipin ammonolysis impurity is obtained after oriented synthesis. The preparation method has the advantages ofmild reaction condition, simplicity and easiness in operation, easiness in separation of target products, and high yield and purity of the products. After the obtained azelnidipine impurity is determined, the accurate content of the azelnidipine impurity in crude drugs can be reflected accurately; the known impurity can be composited into an impurity comparison product in an oriented way, the accurate content of the impurity in the crude drugs can be calculated according to an external standard method and the like, and the azelnidipine impurity has positive significance in purity control of the crude drugs.
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Paragraph 0039; 0040; 0041
(2018/11/22)
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- Synthesis of new 2-substituted pyrido[2,3-d]pyrimidin-4(1H)-ones and their antibacterial activity
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2-Substituted-5,7-dimethyl pyrido[2,3-d]pyrimidin-4(1H)-ones (8) were synthesized by oxidation of 2-substituted-5,7-dimethyl dihydropyrido[2,3-d]pyrimidin-4(1H)-ones (7) which were in turn prepared from 2-amino-4,6-dimethyl nicotinamide (5) and substituted aryl aldehydes (6). 2-Amino-4,6-dimethyl nicotinamide (5) was prepared from ethyl cyanoacetate (1) via malonamamidine hydrochloride (3). The compounds were characterized by IR, NMR, MS and elemental analyses. Compounds 7 and 8 were screened for antibacterial activity against Gram positive and Gram negative bacteria. Dehydrogenated compounds (8) showed less antibacterial activity than the compounds 7. Among all the test compounds screened for antibacterial activity 7c (1.25 μg/ml) showed greater activity. All the synthesized compounds were found inactive when screened for antifungal activity at the concentration of 200 μg/ml.
- Lakshmi Narayana,Raghu Ram Rao,Shanthan Rao
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experimental part
p. 1369 - 1376
(2009/09/27)
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- Inhibitors of the advanced glycosylation of proteins and methods of use therefor
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The present invention relates to compositions and methods for inhibiting nonenzymatic cross-linking (protein aging). Accordingly, a composition is disclosed which comprises an agent capable of inhibiting the formation of advanced glycosylation endproducts of target proteins by reacting with a carbonyl moiety of an early glycosylation product of such target proteins resulting from their initial glycosylation. The method comprises contacting the target protein with the composition. Both industrial and therapeutic applications for the invention are envisioned, as food spoilage and animal protein aging can be treated.
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- Xanthine oxidase (XO): Relative configuration of complexes formed by the enzyme, 2- or 8-N-alkylhypoxanthines and 2-N-alkyl-8-azahypoxanthines. XII
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Several 2- or 8-n-alkyl-hypoxanthines and a 2,8-di-n-pentylhypoxanthine were synthesized and tested as substrates or inhibitors of Xanthine Oxidase (XO). 8-Alkyl derivatives showed a substrate behaviour, whereas 2-alkyl substituted compounds were non-substrates and inhibitors. 2,8-di-n-pentylhypoxanthine was ineffective as inhibitor. The comparison between their activity allowed us to conclude that the complexes formed by the enzyme and the cited n-alkylhypoxanthines or 2-n -alkyl-8-azahypoxanthines involve their N(3) and N(9) positions in all the cases. The position of the n-alkyl chain determines the disposition of the molecule inside the complex: 2-n-alkyl-hypoxanthines and 2-n-alkyl-8-azahypoxanthines gave complexes with the same orientation of heterocyclic moieties, opposite that given by 8-n-alkyl-hypoxanthines.
- Biagi,Giorgi,Livi,Scartoni,Tonetti,Lucacchini
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p. 357 - 374
(2007/10/02)
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- Inhibitors of the advanced glycosylation of proteins and methods of use therefor
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The present invention relates to compositions and methods for inhibiting nonenzymatic cross-linking (protein aging). Accordingly, a composition is disclosed which comprises an agent capable of inhibiting the formation of advanced glycosylation endproducts of target proteins by reacting with the carbonyl moiety of the early glycosylation product of such target proteins formed by their initial glycosylatin. The method comprises contacting the target protein with the composition. Both industrial and therapeutic applications for the invention are envisioned, as food spoilage and animal protein aging can be treated.
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