Venkata Swamy Tangeti*, K. Ramesh Babu, K. V. V. V Satyanarayana, Dasari Vasundhara, Himabindu Mylapalli and Kaja Srinivas Pavan Kumar
Aim and objective: In the work, we have successfully presented a synthetic route for the synthesis of novel 2′,4′-dihydrospiro[chroman-2,3′-pyrazol]-4-one derivatives via one pot multicomponent approach Material and method: Substituted 2′,4′-dihydrospiro[chroman-2,3′-pyrazol]-4-one were prepared through cascade three-component condensation of ortho-hydroxyacetophenone, β-ketoester, hydrazine in presence of pyrrolidine as a catalyst under ethanol reflux conditions. Results: A series of novel 2′,4′-dihydrospiro[chroman-2,3′-pyrazol]-4-one have been synthesized through a facile strategy. These structures of newly synthesized derivatives were determined by 1H, 13C NMR, HRMS and CHNS analysis. Conclusion: We have achieved the one-pot, three-component synthesis of highly substituted pyrazole spirochromanones in presence of pyrrolidine as a catalyst under ethanol reflux conditions. Using different types of aliphatic and aromatic β-ketoesters, o-hydroxyacetophenone derivatives and different kinds of hydrazine derivatives as building blocks, we could construct novel libraries of substituted pyrazole spirochromanones that make this method suitable for combinatorial and parallel synthesis in drug discovery.
Ethylacetoacetate, hydrazine, o-hydroxy acetophenone, pyrazole spirochromanone, one pot.
Jawaharlal Nehru Technological University, Kakinada, Dakamarri, Bimili Mandal, Vishakapatnam – 531162, Department of chemistry, Sri Venkateswara University, Tirupathi, Department of chemistry, Raghu Engineering College, Visakhapatnam 531162, Andhra Pradesh, Department of Chemistry, Raghu Institute of Technology, Dakamarri, Bimili Mandal, Visakhapatnam – 531162, Department of chemistry, Raghu Engineering College, Visakhapatnam 531162, Andhra Pradesh, GVK Biosciences Private Limited, Hyderabad, Telangana 500076