Lemon Juice Mediated Reaction under Ultrasound Irradiation: Synthesis of Indolofuroquinoxalines as Potential Anticancer Agents.

BACKGROUND: A non-hazardous synthetic methodology has been developed for the preparation of compounds based on indolofuroquinoxaline framework. Lemon juice that is known to play the role of a biocatalyst in various organic reactions was used for this purpose. METHOD: A number of indolofuroquinoxaline derivatives were prepared via the lemon juice mediated condensation of methyl 2-(2-chloro-1H-indol-3-yl)-2-oxoacetate or its N-alkyl derivatives with 1,2- diamines under ultrasound irradiation. All the synthesized compounds were screened via an MTT assay for their potential anticancer properties in vitro using a number of cancer cell lines including MDA-MB 231, and MCF7, K562, Colo-205 and IMR-32 and the non-cancerous HEK293 cell line. Compounds 3a, 3b and 3c showed promising growth inhibition against K562, MDA-MB 231 and MCF7 cell lines but no significant effects on HEK293 cell line suggesting their selectivity towards cancer cells. RESULTS AND CONCLUSION: Moreover, according to their IC50 values, all these compounds appeared to be relatively more potent towards K562 cell line over MDA-MB 231 and MCF7 cell lines indicating their potential against leukemia.

Ultrasound Assisted Synthesis of 3,4-Diyne Substituted Isocoumarin Derivatives: Identification of Potential Cytotoxic Agents.

BACKGROUND: The 3,4-diyne substituted isocoumarins have been designed, synthesized and explored as potential anti-proliferative agents. METHOD: Ultrasound assisted synthesis of these compounds was carried out by using a three-step method involving (i) Pd/C-Cu catalyzed cross-coupling between the methyl 2-iodobenzoate and buta- 1,3-diynylbenzene followed by (ii) I2-mediated electrophilic cyclization of the resultant 2-(alk-1- ynyl)benzoate ester and (iii) subsequent alkynylation of 4-iodo-3-(phenylethynyl)-isocoumarin under Pd/C-Cu catalysis. CONCLUSION: The synthesized compounds showed promising growth inhibition when tested against MDA-MB 231 and K562 cancer cell lines.

Ultrasound Assisted One-pot and Sequential Synthesis of 3-methylene-isoindolin-1-ones and their in vitro Evaluation.

BACKGROUND: 3-Methyleneisoindolin-1-one derivatives containing a pyridin-2-ylmethyl substituent on their ring nitrogen were designed as potential bioactive agents. A one-pot synthesis of these compounds was achieved via sequential C-C coupling, followed by C-Si bond cleavage and subsequent tandem C-C/C-N bond forming reaction under ultrasound irradiation. METHOD: The methodology involved coupling of (trimethylsilyl)acetylene with iodoarenes in the presence of 10% Pd/C-CuI-PPh3-Et3N in MeOH followed by treating the reaction mixture with K2CO3 in aqueous MeOH, and finally coupling with 2-iodo-N-(pyridin-2-ylmethyl)benzamide. The in vitro evaluation of these compounds was performed to identify some initial hit molecules one of which showed dose dependent inhibition of PDE4B.

Ultrasound Assisted Synthesis of Quinoline Derivatives in the Presence of SnCl2·2H2O as a Precatalyst in Water: Evaluation of their Antibacterial Activities.

BACKGROUND: SnCl2·2H2O has been used as a convenient precatalyst for the one-pot and rapid synthesis of 2-substituted quinolines under ultrasound irradiation in water. The reaction involved a 3-component reaction of aniline, aldehydes, and ethyl 3,3-diethoxypropionate in the presence of aerial oxygen to give the desired products in good yields. CONCLUSION: Several of these compounds showed antibacterial activities when tested against gram-positive and gram-negative species. One compound i.e. 4b showed promising activities across both the species.

Synthesis of 2H-1,3-benzoxazin-4(3H)-one derivatives containing indole moiety: their in vitro evaluation against PDE4B.

A number of 2H-1,3-benzoxazin-4(3H)-one derivatives containing indole or benzofuran moieties were synthesized by using Pd/C-Cu mediated coupling-cyclization strategy as a key step. The o-iodoanilides or o-iodophenol were coupled with 3-{2-(prop-2-ynyloxy)ethyl}-2H-benzo[e][1,3]oxazin-4(3H)-one using 10%Pd/C-CuI-PPh3 as a catalyst system and Et3N as a base to give the target compounds. All the synthesized compounds were tested for their PDE4B inhibitory potential in vitro using a cell based cAMP reporter assay. Some of them showed fold increase of the cAMP level when tested at 30 µM. A representative compound showed encouraging PDE4B inhibitory properties that were supported by its docking results.