@article {46604, title = {Green catalyst Fe(OTs)(3)/SiO2 for the synthesis of 4-Pyrrolo-12-oxoquinazolines}, journal = {ChemistrySelect}, volume = {5}, year = {2020}, month = {DEC}, pages = {14721-14728}, type = {Article}, abstract = {

An efficient and eco-friendly diversity-oriented synthetic protocol has been presented to synthesize structurally versatile drug-like molecules under solvent-free grinding in the presence of Fe(OTs)(3)/SiO2 as a catalyst. The use of Fe(OTs)(3)/SiO2 as a recyclable and reusable catalyst has been explored in the synthetic domino protocol involving one-pot, three component reaction for the synthesis of 4-pyrrolo-12-oxoquinazolines with special features of the protocol like high atom-economy, operational simplicity, short reaction time and high selectivity with excellent yields.

}, keywords = {4-Pyrrolo-12-oxoquinazolines, Fe(OTs)(3), Green methodology, Liquid Assisted Grinding (LAG), SiO2 catalyst, Solvent-free grinding}, issn = {2365-6549}, doi = {10.1002/slct.202004012}, author = {Allaka, Bhargava Sai and Basavoju, Srinivas and Krishna, Gamidi Rama} } @article {47687, title = {Photoinduced multicomponent regioselective synthesis of 1,4,5-trisubstituted-1,2,3-triazoles: transition metal-, azide- and oxidant-free protocol}, journal = {Advanced Synthesis \& Catalysis}, volume = {363}, year = {2021}, month = {JUL }, pages = {3560-3565}, type = {Article}, abstract = {A transition metal- and azide-free approach is explored to synthesize 1,4,5-trisubstituted-1,2,3-triazoles under sunlight. The reaction proceeds via C-N and N-N bond formations. These regioselective 1,2,3-triazoles are obtained from isatin Schiff bases, benzaldehydes and tosylhydrazine in the presence of base. This protocol offers the structurally diverse 1,2,3-triazole derivatives with 75-90\% yields.}, keywords = {1, 2, 3-triazoles, 4, 5-trisubstituted-1, azide- and oxidant free protocol, Cycloaddition, milder reaction conditions, molecular diversity, Multicomponent reaction, Regioselectivity, transition metal-}, issn = {1615-4150}, doi = {10.1002/adsc.202100321}, author = {Sai Allaka, Bhargava and Basavoju, Srinivas and Rama Krishna, Gamidi} } @article {47896, title = {Transition metal- and oxidant-free regioselective synthesis of 3,4,5-trisubstituted pyrazoles by means of [3+2] cycloaddition reactions}, journal = {ChemistrySelect}, volume = {7}, year = {2022}, month = {MAR}, pages = {e202200605}, type = {Article}, abstract = {

A highly efficient regioselective synthesis of 3,4,5-trisubstituted pyrazoles via transition metal- and oxidant-free, three component [3+2] cycloaddition with thiazolidinedione chalcones, benzaldehydes and N-tosylhydrazine is described. The reaction proceeds through C-C and C-N bond formations under mild reaction conditions to produce structurally diverse polysubstituted pyrazoles in moderate to good yields.

}, keywords = {3, 4, 5-trisubstituted pyrazoles, Cycloaddition, Multicomponent reaction, Oxidant free, Regioselectivity, Transition metal free}, issn = {2365-6549}, doi = {10.1002/slct.202200605}, author = {Allaka, Bhargava Sai and Basavoju, Srinivas and Gamidi, Rama Krishna} } @article {48467, title = {Ultrasound assisted green protocol for the synthesis of quinoxaline based bisspirooxindoles: crystal structure analysis, enone umpolung, DFT calculations, anti-cancer activity, and molecular docking studies}, journal = {Synthetic Communications}, volume = {53}, year = {2023}, month = {JUN}, pages = {835-854}, type = {Article}, abstract = {

A series of novel quinoxaline based bisspirooxindolo-pyrrolizidines were synthesized through 1,3-dipolar cycloaddition under ultrasonication with shorter reaction time and good yields. The compounds were well characterized by various spectroscopic methods and finally single crystal X-ray diffraction method (4c, 4d). DFT energy calculations confirm the regioselectivity due to enone umpolung effect. The in vitro anti-cancer activity of the synthesized compounds (4a-s) shows that the compounds 4g and 4q exhibited good anti-cancer activity with IC50 values14.51 +/- 1.1 and 11.36 +/- 0.23 mu M against DU-145 prostate cancer cell line; and 16.78 +/- 0.95 and 14.28 +/- 0.64 mu M against Hela cervical cancer cell lines when compared to the standard anti-cancer drug doxorubicin (1.75 +/- 0.06 and 1.35 +/- 0.09 mu M). In silico molecular docking studies indicated that the synthesized compounds may serve as a potential lead for the further development of novel anti-cancer agents.

}, keywords = {Anti-cancer activity, bisspirooxindoles, DFT calculations, Hirshfeld surface, ultrasonication}, issn = {0039-7911}, doi = {10.1080/00397911.2023.2199360}, author = {Baddepuri, Sravanthi and Allaka, Bhargava Sai and Gamidi, Rama Krishna and Faizan, Mohmmad and Pawar, Ravinder and Basavoju, Srinivas} } @article {48296, title = {Ultrasound assisted synthesis of spirooxindolo-1,2,4-oxadiazoles via [3+2] cycloaddition reaction and their anti-cancer activity}, journal = {ARKIVOC}, year = {2023}, month = {MAY}, pages = {S1-S46}, type = {Article}, issn = {1551-7004}, author = {Kanchrana, Madhu and Allaka, Bhargava Sai and Krishna, Gamidi Rama and Basavoju, Srinivas} } @article {48972, title = { Ultrasound assisted synthesis of spirooxindolo-1,2,4-oxadiazoles via [3+2] cycloaddition reaction and their anti-cancer activity}, journal = {Arkivoc}, year = {2023}, pages = {Special Issue}, type = {Article}, issn = {1551-7004}, author = {Kanchrana, Madhu and Allaka, Bhargava Sai and Krishna, Gamidi Rama and Basavoju, Srinivas} } @article {49090, title = {Ultrasound-assisted ionic liquid-mediated green method for synthesis of 1,3-diphenylpyrazole-based spirooxindolopyrrolizidines, their anti-tubercular activity, molecular docking study and ADME predictions}, journal = {New Journal of Chemistry}, volume = {48}, year = {2024}, month = {JUN }, pages = {9970-9980}, type = {Article}, abstract = {

The aim of the study is to develop the synthesis of a novel series of potent anti-tubercular (anti-TB) activity of 1,3-diphenylpyrazole-based spirooxindolopyrrolizidine derivatives via an efficient green approach achieved by using an ionic liquid ([Bmim]BF4) under ultrasonication. The title compounds 4a-4ad with a general molecular formula CaHbX(0-2)NcOd (X = F/Cl/Br) were produced with high yields in shorter reaction time and well characterized by using spectral techniques; and finally single crystal X-ray diffraction method (4b). The newly synthesized compounds were evaluated for their in vitro anti-TB activity against Mycobacterium tuberculosis H37Rv strain. Among all, six compounds 4e (C36H29N5O4), 4g (C34H28N4O3), 4q (C36H28F2N4O2), 4r (C36H28ClFN4O2), 4y (C36H29BrN4O2) and 4z (C36H28BrFN4O2) exhibited significant anti-TB activity with MIC value 6.25 mu g mL-1, when compared to the standard drug ethambutol (MIC:1.56 mu g mL-1). In silico molecular docking studies were performed against M. tuberculosis enoyl-acyl carrier protein reductase inhibitor. The compounds 4o, 4p, 4y and 4aa were exhibited least binding energies -12.58, -12.61, -12.58 and -12.57 kcal mol-1, respectively. These results reveal that the produced compounds might be used for the future generation of novel anti-TB drugs. The study aims to develop and synthesis of a novel series of 1,3-diphenylpyrazole-based spirooxindolopyrrolizidine derivatives as potent anti-TB agents via an efficient green approach by using an ionic liquid ([Bmim]BF4) under ultrasonication.

}, issn = {1144-0546}, doi = {10.1039/d4nj00563e}, author = {Baddepuri, Sravanthi and Gamidi, Rama Krishna and Kumari, Jyothi and Sriram, Dharmarajan and Basavoju, Srinivas} }