| abstract |
In the preparation of zolmitriptan of formula III the reduction of the diazonium salt to (5)-4-(4- hydrazinobenzyl)-l,3-oxazolidin-2-one of formula IV is performed in a more concentrated mixture and by the effect on an alkali metal disulphite, preferably sodium disulphite. A zolmitriptan toluene solvate, characterized by a toluene content of 9 to 14 % by weight according to the gas chromatography determination and by a maximum of the corresponding mass loss at temperatures of about 111°C in the gravimetric analysis record. A zolmitriptan toluene solvate, showing strong Raman bands at the wave numbers of 1443 and 1354 cm-1, characteristic for the crystal lattice of zolmitriptan with built-in toluene, and further marked bands at 1004 and 786 cm-1, characteristic for toluene. |