Regioselective hydrostannation of diarylalkynes directed by a labile ortho bromine atom: An easy access to stereodefined triarylolefins, hybrids of combretastatin A-4 and isocombretastatin A-4

Abstract

A series of triarylolefins bearing the combretastatin A-4 and the isocombretastatin A-4 cores were synthesized and evaluated. The cooperative ortho-effect of a labile bromine atom in the regioselective hydrostannation of unsymmetrical diarylalkynes leading to stereodefined triarylolefins is presented.

Tunable Photochromism in the Robust Dithienylethene‐Containing Phospholes: Design, Synthesis, Characterization, Electrochemistry, Photophysics, and Photochromic Studies

“…P , P ‐Dichlorophenylphosphine, palladium(II) acetate, 4,4′di‐ tert ‐butyl‐2,2′‐bipyridine and (1,5‐cyclooctadiene)(methoxy)iridium(I) dimer were purchased and used as received. Tetrakis(triphenylphosphine)palladium(0)22 as catalyst for Suzuki cross‐coupling, 3‐bromo‐4‐iodobenzotrifluoride,23 3‐bromo‐4‐iodoanisole,24 4,4,5,5‐tetramethyl‐2‐(2,2′′,5,5′′‐tetramethyl‐[3,2′:3′,3′′‐terthiophen]‐5′‐yl)‐1,3,2‐dioxaborolane (Bpin‐thiophene‐DTE)2i and 2‐(5,6‐bis(2,5‐dimethylthiophen‐3‐yl)thieno[3,2‐ b ]thiophen‐2‐yl)‐4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolane (Bpin‐thienothiophene‐DTE)2i were prepared according to literature procedures with slight modifications. THF, diethyl ether, dichloromethane, toluene and hexane were purified using Innovative Technology Inc. Model PureSolv MD 5 solvent purification system and deaerated with prepurified argon gas before use.…”

Design, synthesis and anticancer properties of 5-arylbenzoxepins as conformationally restricted iso combretastatin A-4 analogs

“…In our efforts to discover novel CA-4 analogues having non-isomerizable linkers between the A-and B-rings, [21][22][23][24][25][26], we recently synthesized a series of 1,1-diarylethylene derivatives [27][28][29] with general structure 2. The most active molecules in this series, isoCA-4 (2a), isoNH2CA-4 (2b), isoFCA-4 (2c) and 2d displayed a nanomolar level of cytotoxicity against various cancer cell lines, inhibited tubulin polymerization (ITP) at a micromolar level, and arrested cancer cells in the G2/M phase of the cell cycle ( Figure 1).…”

Supramolecular Interactions of Terpyridine-Derived Cores of Metallomesogen Precursors

“…[2,2′:6′,2″]terpyridine-4′-ol [19], 2,6-di(pyridin-2-yl)pyridin-4-yl trifluoromethane-sulfonate [20], 5-ethynyl-1,2,3-trimethoxybenzene [21], and 5-(bromomethyl)-1,2,3-trimethoxybenzene [22] were prepared by literature procedures.…”