sAJM589

A rapid, efficient, and environmentally benign procedure for the synthesis of novel furo [2,3-c]phenazine derivatives has been developed via reactions of 2-hydroxynaphthalene-1,4-dione, arylglyoxals, and indole in the presence of TiO2-SO3H-catalyst (TSAC) as a recyclable heterogeneous catalyst under solventfree conditions using microwave irradiation.

This study describes a successful approach for the synthesis of 2-(4-bromophenyl)-1-(1H-indol-3- yl) benzo[a]furo[2,3-c] phenazine in the presence of TiO2-SO3H-catalyst using microwave irradiation.

In this paper, we report an efficient and convenient method for the synthesis of phenazine derivatives from benzo[a]phenazin-5-ol, arylglyoxal derivatives, and indoles in the presence of TiO2-SO3H-catalyst under microwave irradiation.

All reagents and solvents were purchased from Merck and Aldrich and used without further purification. 1H NMR spectra (DMSO) were recorded on the Gemini-500 MHz spectrophotometer with TMS as an internal standard.

To investigate the reaction conditions for the synthesis of 2-(4-bromophenyl)-1-(1Hindol- 3-yl) benzo[a]furo [2, 3-c] phenazine derivatives, we performed a reaction between 2-hydroxynaphthalene- 1,4-dione (1 mmol) and aromatic 1,2-diamines (1 mmol) as a model.

We demonstrated a green and straightforward procedure for the efficient synthesis of novel benzo[ a]furo[2, 3-c] phenazine derivatives in high yields via a one-pot, four-component domino protocol by using TiO2-SO3H as a mild, effective, non-toxic, and inexpensive solid acid catalyst without the addition of an organic co-solvent.

A new one-pot three-component reaction for the synthesis of benzo[a]pyrano[2,3-c]phenazine derivatives I [R = H, 4-Cl, 3,4,5-(MeO)₃, etc.] has been developed.The synthesis was achieved by reacting benzo[a]phenazin-5-olwith substituted benzaldehydes and (E)-N-methyl-1-(methylthio)-2-nitroethenamine at 120°C under neat reaction conditions.This transformation involved the formation of the pyranophenazine ring by creation of two C-C bonds and one C-O bond in a single synthetic operation.As the products precipitate out of the reaction, simple filtration is sufficient to isolate the products and hence, there is no need for work-up or column-chromatog. purificationAll the synthesized compounds were tested in-vitro for their antiproliferative activity against four cancer cell lines, namely DU 145 (prostate cancer), MDA-MB-231 (breast cancer), SKOV3 (ovarian cancer), and B16-F10 (skin cancer).Some of these compounds exhibited good activity against B16-F10 cell line.Notably, compounds I [R = 4-Cl, 4-CN] showed the most potent activity against B16-F10 cells with an IC₅₀ value of 0.31, 0.11μM, resp., compared to the standard drug Doxorubicin.Furthermore, mol. docking studies of I [R = 4-Cl, 4-F] revealed that these active compounds binded in the ATP-binding site of ERK2 receptor.