Niu, Qingqing published the artcileIsatins 3-C annulation vs ring-opening: Two different pathways for synthesis of spiro compounds via multicomponent reactions, Application In Synthesis of 1076-59-1, the publication is Tetrahedron Letters (2019), 60(43), 151181, database is CAplus.
An efficient synthesis of spiro compounds I (R1 = 5-CH3, 7-Br, 6-Cl, etc.; R2 = H, Me; R3 = H, Ph), II [R3 = 7-CF3, 5,7-(Me)2, 7-I, etc.; R4 = H, Me], III and IV (R3 = H) via two different pathways from the reactions of isatins, 3-phenylisoxazol-5(4H)-one, (3-ethylisoxazol-5(4H)-one) and pyrazol-5-amine, (6-aminopyrimidine-2,4(1H,3H)-dione) was reported. The catalyst Amberlyst-15 could be easy recycled and reused for many time without any appreciable loss in catalytic activity. The new type spiro compounds were gained through the ring-opening of isatins process. The structures of spiro[indoline-3,4′-isoxazolo[5,4-b]pyrazolo[4,3-e]pyridin]-2-one, spiro[isoxazolo[5,4-b]quinoline-4,5′-pyrrolo[2,3-d]pyrimidine]-2′,4′,6′(1’H,3’H,7’H)-trione and spiro[indoline-3,4′-pyrazolo[3,4-b]pyridine]-2,6′(5’H)-dione were successfully confirmed by 1H NMR, 13C NMR, HRMS, and X-ray crystal diffraction anal.
Tetrahedron Letters published new progress about 1076-59-1. 1076-59-1 belongs to isoxazole, auxiliary class Oxazoline,Benzene,Ester, name is 3-Phenylisoxazol-5(2H)-one, and the molecular formula is C9H7NO2, Application In Synthesis of 1076-59-1.
Referemce:
https://en.wikipedia.org/wiki/Isoxazole,
Isoxazole | C3H3NO – PubChem