- Synthesis method of 2-amino-4,6-dimethylpyridine
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The invention discloses a synthesis method of 2-amino-4,6-dimethylpyridine. The synthesis method is characterized by comprising the following steps: adding 3-aminocrotononitrile into acetic acid in batches, and carrying out heating for ripening; cooling a reaction liquid, and beginning to decompress and concentrate acetic acid; then adding a concentrated solution into crushed ice, and carrying outsuction filtration, suspension washing and drying on a separated solid to obtain an intermediate; adding the intermediate into a concentrated sulfuric acid solution, and carrying out heating for ripening; carrying out cooling, and dropwise adding pure water for a quenching reaction; pouring a reaction liquid obtained in the previous step into crushed ice, then adding methylbenzene for extractionmultiple times, combining upper-layer organic phases, and sequentially performing washing with saturated sodium chloride, drying, suction filtration and concentration to obtain a crude product; carrying out reduced-pressure solid distillation on the crude product, and collecting a product fraction; and recrystallizing the obtained fraction by using isopropyl ether so as to obtain the white crystalline 2-amino-4,6-dimethylpyridine. According to the prepared high-purity 2-amino-4,6-dimethyl pyridine, GC purity can reach 99% or above, and total yield is 70% or above.
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Paragraph 0021-0025; 0033-0036
(2020/07/15)
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- THERAPEUTIC INHIBITORY COMPOUNDS
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Provided herein are heterocyclic derivative compounds and pharmaceutical compositions comprising said compounds that are useful for inhibiting plasma kallikrein. Furthermore, the subject compounds and compositions are useful for the treatment of diseases wherein the inhibition of plasma kallikrein inhibition has been implicated, such as angioedema and the like.
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Paragraph 00123
(2017/01/26)
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- TRICYCLIC PYRAZOLOPYRIDINE COMPOUNDS
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In one aspect this invention relates generally to compounds of Formula I and sub-formulas thereof, or a tautomer of each thereof, a pharmaceutically acceptable salt of each thereof, or a pharmaceutically acceptable solvate of each of the foregoing, where
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Paragraph 0119
(2015/11/27)
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- PYRAZOLOPYRIDINE PYRAZOLOPYRIMIDINE AND RELATED COMPOUNDS
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In one aspect this invention relates generally to compounds of Formula: and sub-formulas thereof, or a tautomer of each thereof, a pharmaceutically acceptable salt of each thereof, or a pharmaceutically acceptable solvate of each of the foregoing, where X1, L1, L3, and R3 are described herein.
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Paragraph 0250; 0251
(2015/11/25)
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- THERAPEUTIC INHIBITORY COMPOUNDS
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The invention provides compounds of Formula I and Formula II: A-B-C-D-E-F-G-J (I) C-D-E-F-G-J (II) wherein A, B, C, D, E, F, G, and J have any of the values defined in the specification, and salts thereof. The compounds are useful for inhibiting plasma kallikrein, and for treating a disease or condition in an animal where inhibition of plasma kallikrein is indicated.
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- Pyrolytic methods in organic synthesis: Novel routes for the synthesis of 3-oxoalkanenitriles, 2-acyl anilines, and 2-aroyl anilines
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3-Oxoalkanenitriles 1a-d were obtained in high yield by treating enaminones 6a-d with hydroxylamine hydrochloride and stirring the resulting oxime with diethyl oxalate. The formed 3-oxoalkanenitriles 1a,b readily undergo self-condensation to yield 2-aroylanilines 3a,b on heating in pyridine for eight hours or by irradiation in microwave for 1.5 minutes. In contrast, 1c-e were recovered unreacted under similar conditions. Pyrolysis of 3-aminocrotononitrile 14 produced a mixture of the aminopyridine 16, 19, and aminobenzene 22. Heating 14 in aqueous media has resulted in formation of the pyridine 20, while heating the same compound in acetic acid has afforded pyridone 20 and acetyl pyridine 24. Georg Thieme Verlag Stuttgart.
- Al-Awadi, Nouria A.,Abdelkhalik, Mervat M.,Abdelhamid, Ismail A.,Elnagdi, Mohamed H.
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p. 2979 - 2982
(2008/03/12)
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