Isothiazole

Isothiazole is a colorless liquid with a pyridine-like odor. It is only slightly soluble in water but readily dissolves in organic solvents such as ethanol and benzene. When treated with butyl lithium at -70°C, it undergoes lithiation at the 5-position. Isothiazole serves as a versatile intermediate for the synthesis of various 5-substituted derivatives, including alkyl groups (R-), formyl (-CHO), carboxyl (-COOH), and acyl groups (RCO-), among others. Electrophilic substitution reactions, such as nitration, sulfonation, and halogenation, predominantly occur at the 4-position.

Isothiazole, is a versatile building block that can be used in the synthesis of more complex compounds with biological activity such as the pharmaceutical drugs ziprasidone (Z485000), and perospirone (P288900).

ChEBI: Isothiazole is a mancude organic heteromonocyclic parent, a monocyclic heteroarene and a member of 1,2-thiazoles.

Isothiazole can be prepared by the reaction of propiolic aldehyde with sodium thiocyanate to first produce 3-thiocyanatoacrolein (NCSCH=CHCHO), which is then reacted with ammonia to obtain isothiazole.

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