Ethanol → HCID 178461156, compound

Participants

Reaction Steps

Doxycycline p-toluenesulphonate (40.0 g) prepared according to the process above was suspended in a mixture of ethanol (72.0 ml) and water (24.0 ml), with stirring. A solution of triethylamine (9.04 ml) in ethanol (9.04 ml) was added, causing dissolution followed by crystallisation. After stirring for 20 minutes, ethanol (144 ml) was added and the mixture stirred for a further 1 hour 30 minutes. The crystals were filtered, washed with ethanol (25 ml), then with acetone (12.5 ml) and dried at 35° C. The product, doxycycline monohydrate, weighed 22.12 g and complied with the U.S. Pharmacopoeia monograph requirements. The mother liquors were diluted with an equal volume of water and 5-sulphosalicylic acid (2.0 g) was added. After stirring overnight, the deposited solid was filtered, washed with 66% aqueous methanol and then with acetone, dried at 35° C., and gave 1.53 g of doxycycline sulphosalicylate.

Provenance & Evidence