Reaction of isothiourea with 2,3-diaza-3-pentenedioic anhydride. A solid-phase synthesis of 3-amino-1,2,4-triazin-5(4H)-ones

The first reported solid-phase synthesis of 3-amino-1,2,4-triazin-5(4H)-ones is described. Reactions of polymer-bound isothiourea with 2,3-diaza-3-pentenedioic anhydride forms 3-amino-1,2,4-triazin-5(4H)-ones in good yields and high purity.