5 -diphosphate monohydrate. crystal

Dehydration of hydrates can also lead to the formation of unique crystals. Caffeine Form II was prepared by recrystallizing caffeine from water, drying for 8 days at 30°C, and then heating for 4 hours at 80°C [38]. Chloroquine diphosphate 3 1 hydrate was converted to the anhydrous form at temperatures above 188°C [49]. Etoposide Form I (a monohydrate) was found to undergo a dehydration reaction in the temperature range of 85-115°C to yield etoposide Form la. This form could be melted at 198°C and transformed to etoposide Form Ila, which itself melted at 198°C and crystallized to still another polymorph, etoposide Form Ila at 206°C. Etoposide Form Ila was found to melt at 269°C and convert to its hydrated form, etoposide Form n, when exposed to the atmosphere at room temperature. This hydrate was also found to undergo a dehydration reaction at 90-120°C to yield etoposide Form Ila [50]. 

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