ChemicalBook CAS DataBase List Meloxicam

Meloxicam synthesis

10synthesis methods

Product Name:Meloxicam
CAS Number:71125-38-7
Molecular formula:C14H13N3O4S2
Molecular Weight:351.4

It can be synthesized in four steps from benzisothiazolo-3(2H)-one-1,1-dioxide. Reaction of benzothiazolo-3(2H)-one-1,1-dioxide with methyl chloroacetate gives the methyl 2(3H)-acetate derivative, which is isomerized with sodium methoxide in toluene-tert-butanol yielding methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide. Subsequent methylation with methyl iodide in methanol yields the 2-methyl compound. Finally this compound is treated with 2-amino-5-methylthiazole in xylene.

2H-1,2-Benzothiazine-3-carboxamide, 4-hydroxy-2-methyl-N-(5-methyl-2-thiazolyl)-, 1,1-dioxide, potassium salt, hydrate (1:1:1)

892395-40-3
1 suppliers
inquiry

71125-38-7
597 suppliers
$11.00/5g

Yield:71125-38-7 98.5%

Reaction Conditions:

Stage #1: meloxicam potassium salt monohydratewith potassium hydroxide;pyrographite in ethanol;water at 40 - 45; for 0.666667 h;
Stage #2: with acetic acid in ethanol;water at 10 - 30; pH=3 - 5; for 2.5 h;Product distribution / selectivity;

Steps:

4

One proceeds according to Example 2 with the only difference that the solution of the potassium salt is treated with 6.0 ml 96% acetic acid instead of hydrochloric acid.

References:

WO2006/64298,2006,A1 Location in patent:Page 24

7305-71-7 Synthesis