Synthesis of some new 2-[2, 4′-Dioxo Spiro Indole -3, 2′- Thiazolidin- 3′-yl] Alkanoic Acids as Potential Fungicidal Agents

2-[2, 4′-dioxo spiro indole -3, 2′- thiazolidin- 3′-yl] alkanoic acids (2) have been prepared by refluxing 2-indolone-3-yl imino alkanoic acid (1) with mercapto acetic acid in 1, 4-dioxan. The compounds prepared were screened for their fungicidal activity against Pyricularia oryzae, Puccinia graminis, Alternaria solani and Phytopthora infestans.