79025-28-8Relevant articles and documents
Preparation method of 3-hydroxy-4-methoxy-2-nitrobenzoic acid
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Paragraph 0064-0068, (2020/07/12)
The invention discloses a preparation method of 3-hydroxy-4-methoxy-2-nitrobenzoic acid, and belongs to the field of synthesis of medical intermediates. The preparation method comprises the followingsteps: starting from 3-alkoxy-4-acetoxybenzaldehyde (1), carrying out a nitration reaction process to obtain an intermediate (2), removing acetyl from the intermediate (2) to obtain an intermediate (3), methylating to obtain an intermediate (4), oxidizing the intermediate (4) to obtain an intermediate (5), deprotecting the intermediate (5), and recrystallizing to remove the isomer, thereby obtaining the 3-hydroxy-4-methoxy-2-nitrobenzoic acid (6). The method is simple, convenient and stable to operate, high in yield, environment-friendly, low in production cost and suitable for industrial large-scale production, and products in all steps are easy to separate.
NOVEL BICYCLIC ANTIBIOTICS
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Page/Page column 120-121, (2010/08/08)
Compounds of formula (I) wherein X1, X3; X4 and X6, each independently of the others, represents a nitrogen atom or CR2, with the proviso that at least one of X1, X3; X4 and X6 represents a nitrogen atom; X2 represents C-H, C-(C1-C6alkyl), C-(C1-C6alkoxy), C-halogen, C-COOH; X5 represents C-H or C-(C1-C6alkyl), C-halogen; R1 and R2, independently of one another, represent hydrogen or a substituent selected from hydroxy, halogen, carboxy, amino, C1-C6alkylamino, di(C1-C6alkyl)amino, mercapto, cyano, nitro, C1-C6alkyl, C1-C6alkoxy, C1-C6alkylthio, C1-C6alkylamino- carbonyloxy, C2-C6alkenyl, C2-C6alkynyl, C1-C6alkylcarbonyloxy, C1-C6alkyl- sulfonyloxy, C1 -C6heteroalkylcarbonyloxy, C5-C6heterocyclylcarbonyloxy, C1-C6heteroalkyl, C1-C6heteroalkoxy, wherein heteroalkyl, heteroalkoxy groups or heterocyclyl comprise 1, 2 or 3 heteroatoms selected from nitrogen, oxygen and sulphur, in which substituents the alkyl moieties are unsubstituted or further substituted by halogeno, cyano, hydroxy, C1-C4alkoxy, C1-C4alkylcarbonyl, C1-C4alkoxycarbonyl, unsubstituted or substituted phenoxy or phenylcarbonyl, unsubstituted or substituted C5-C6heterocyclyl or carboxy; A1 represents a divalent group of one of the formulae -O-(CH2)m-(CH2)-, -S-(CH2)m-(CH2)- or -(C=O)O-(CH2)m-(CH2)-, wherein the (CH2)m moiety is optionally substituted by C1-C4alkyl, C2-C4alkenyl, C3-C6cycloalkyl, C3-C6cycloalkylmethyl, morpholinomethyl, halogen, carboxy, hydroxy, C1-C4alkoxy; C1 -C4alkoxyC1 -C4alkyl, C1 -C4alkoxy(C1 -C4alkylenoxy)C1 -C4alkyl, benzyloxyC1 - C4alkyl, amino, mono- or di-(C1-C4alkyl)amino or acylamino, in which substituents the alkyl moieties can be further substituted by 1 or more fluoro atoms m is 0, 1 or 2, provided that the number of atoms in the direct chain between the two terminal valencies of A1 is at least 3, which group A1 is linked to A2 via the terminal (CH2)-moiety; A2 is a group selected from C3-C8cycloalkylene; saturated and unsaturated 4 to 8- membered heterocyclodiyl with 1, 2 or 3 heteroatoms selected from nitrogen, oxygen and sulphur, which group A2 is unsubstituted or substituted; R4 represents hydrogen or C1 -C4alkyl; A3 represents C1-C4alkylene, C2-C4alkenylene, >C=O, -C(O)C1-C3alkylene-, -C(=O)NH-, or a group selected from -C2H4NH-, -C2H4O-, and -C2H4S- being linked to the adjacent NR4-group via the carbon atom; and G represents aryl or heteroaryl, which is unsubstituted or substituted and n is 0, 1 or 2; or a pharmaceutically acceptable salts, hydrates or solvates thereof are valuable antibacterial agents.
Alkoxy-substituted-6-chloro-quinazoline-2,4-diones
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, (2008/06/13)
2,4-Diaminoquinazolines of the formula STR1 wherein Y1 is hydrogen or chloro, Y2 is OR, Y3 is hydrogen or OR such that when Y1 is hydrogen, Y3 is OR and when Y1 is chloro, Y3 is hydrogen or OR, and the pharmaceutically acceptable salts thereof; R represents an alkyl group having from one to three carbon atoms; taken separately, R1 and R2 are each hydrogen, alkyl having from one to five carbon atoms, cycloalkyl having from three to eight carbon atoms, alkenyl or alkynyl each having from three to five carbon atoms or hydroxy substituted alkyl having from two to five carbon atoms, when taken together with the nitrogen atom to which they are attached R1 and R2 form a substituted or unsubstituted heterocyclic group optionally containing an atom of oxygen, sulfur or a second atom of nitrogen as a ring member; their use as antihypertensive agents, pharmaceutical compositions containing them and intermediates for their production.
