The mesoionic structure of<unk> <unk>  and linsidomine are sydnone imines, a class of mesoionic heterocyclic aromatic chemical compounds.<unk>  melts at , is freely soluble in chloroform, soluble in aqueous hydrochloric acid, ethanol, ethyl acetate and methanol, sparingly soluble in water and acetone, and very slightly soluble in diethyl ether and petroleum ether. It is stable in aqueous solutions at pH 5–7, but not in alkaline solutions. Its absorption maximum is in the near ultraviolet, at 326 nm, in chloroform. The substance is sensitive to ultraviolet light at wavelengths shorter than 320 nm. Synthesis Synthesis Its synthesis starts by reacting 1-aminomorpholine with formaldehyde and hydrogen cyanide to give 2. Nitrosation gives the N-nitroso analog (3) which cyclizes to the sydnone (4) on treatment with anhydrous acid. Formation of the ethyl urethane is then made possible by reacting linsidomine with ethyl chloroformate.
Molsidomine
Tolperisone
Tilorone
Scopolamine
Clofoctol
Tesofensine
Carctol
Tiratricol