Lepidiline-Derived Imidazole-2(3<i>H</i>)-Thiones: (3+2)-Cycloadditions vs. Nucleophilic Additions in Reactions with Fluorinated Nitrile Imines.

ABSTRACT: Two series of imidazole-2(3H)-thiones inspired by naturally occurring lepidiline alkaloids, bearing either one or two benzyl-type substituents located at the N(1)/N(3) atoms, respectively, were prepared and examined in reactions with in situ generated C-trifluoromethyl-N-aryl nitrile imines. N,N-Dibenzylated imidazole-2-thiones served exclusively as C=S dipolarophiles to afford hitherto unknown CF₃-functionalized spiro [1,3,4-thiadiazole-5,2'-imidazole] derivatives formed through the (3+2)-cycloaddition pathway. In contrast, the enolizable N-monobenzylated imidazole-2-thiones provided acyclic products, i.e., hydrazonothioates, resulting from nucleophilic addition of the respective en(thio)late onto the C-termini of the 1,3-dipole.

SUBMITTER: Poper WK 

PROVIDER: S-EPMC12526023 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature