71489-74-2

Upstream product

• 77-78-1 dimethyl sulfate 
• 881-68-5 vanillin acetate 

Downstream Products

• 128767-72-6 ethyl 2-nitro-3-hydroxy-4-methoxybenzoate 
• 606-59-7 cinnabarinic acid 
• 137152-37-5 1-(3-dimethylaminopropylcarbamoyl)-2-amino-4-methyl-6-methoxy-9-carboxy-3H-3-oxophenoxazine hydrochloride 
• 81325-74-8 2-amino-4,6-dimethyl-1,9-di(3-dimethylaminopropyl)carbamoyl-3H-3-oxophenoxazine dihydrochloride 
• 81914-63-8 N-(2-nitro-3-hydroxy-4-methoxybenzoyl)tris(hydroxymethyl)methylamine 
• 128767-71-5 ethyl 2-amino-3-hydroxy-4-methoxybenzoate 

Relevant academic research and scientific papers

Preparation method of 3-hydroxy-4-methoxy-2-nitrobenzoic acid

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.