The synthesis and characterization of a series of cocrystals of an isoniazid derivative with butan-2-one and propan-2-one.

Four cocrystals containing N'-(butan-2-ylidene)pyridine-4-carbohydrazide (izbt) and one cocrystal containing N'-isopropylideneisonicotinohydrazide (izact) were synthesized by reacting isoniazid with either butan-2-one (for the former) or acetone (for the latter). The coformers used to synthesize the izbt cocrystals were 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2-chloro-4-nitrobenzoic acid and 1-naphthoic acid. 1-Naphthoic acid was also used with izact to form a cocrystal.

Chains or rings? Polymorphism of an isoniazid derivative derivatized with diacetone alcohol.

Isoniazid was derivated with diacetone alcohol in a Schiff-base reaction in order to yield '-[(2)-4-hydroxy-4-methylpentan-2-ylidene]pyridine-4-carbohydrazide. The resulting product was determined to be polymorphic, exhibiting two crystal forms: form I and form II. From the crystal structure determination using SC-XRD it was determined that form I crystalizes in the 2/ space group while form II crystalizes in the 2/ space group.