Domino synthetic approach toward new spirooxindole pyran scaffolds

Due to the necessary need of small molecules containing bioactive heterocycles for biological targets, access to wide compound collections with potential biological activities is highly desirable.1 Heterocyclic spirooxindole pyran are attractive synthetic targets due to their biological activities such as antiviral, antibacterial, antifungal, anti-HIV, and anti-cancer activities.2 With this background for the formation of molecular architectures with wide potential biological activities, here we designed and introduced a new protocol involves four-component reaction of the nitroketene dithioacetals 1, alkylamine/benzylamine 2, isatin 3 and pyrazolone 4 as an enolizable C−H activated compound under mild and catalyst-free conditions leads to new functionalized chiral spirooxindole pyrans named spiro[indoline-3,4'-pyrano[2,3-c]pyrazol] 5 in moderate to good yields (Scheme 1). Prominent advantages of this method are the diversity of molecular structure, easy workup, in the absence of a catalyst and operational simplicity.

کلیدواژه ها:

Spirooxindole ، Pyran ، Catalyst-free approach ، Nitroketene dithioacetals ، Isatin.