3,5‐Bis(arylidene)piperid‐4‐ones Containing 1,3,2‐Oxazaphosphorinane Moieties: Synthesis and Antitumor Activity

Abstract

Two novel series of phosphorus‐substituted 3,5‐bis(arylidene)piperid‐4‐ones bearing 1,3,2‐oxazaphosphorinane cycle either directly attached to the piperidone core through the PN bond (diamidophosphates 4) or connected with it via thiocarbamoyl linker (thioureas 5) were obtained by the phosphorylation of NH precursors with 2‐oxo‐1,3,2‐oxazaphosphorinane chloride or the reaction of the former ones with the corresponding cyclic isothiocyanate. According to the results of cytotoxicity screening against human carcinoma cell lines (A549, CaOv3, KB), thioureas 5 were more active than the diamidophosphates 4 bearing the same arylidene rings, with compounds with electron‐withdrawing side groups displaying IC50 in the micromolar range of 1.2–7 μM. © 2013 Wiley Periodicals, Inc. Heteroatom Chem 24:191–199, 2013; View this article online at http://wileyonlinelibrary.com. DOI 10.1002/hc.21082

Phosphine Oxides as Spectroscopic Halogen Bond Descriptors: IR and NMR Correlations with Interatomic Distances and Complexation Energy

“…For example, in [52,53], the crystal adducts of various phosphine oxides (Ph 2 (Me)P=O, Ph 3 PO) with strong halogen donors such as pentafluoroiodoebenzene C 6 F 5 I and 1,4-diaryl-5-iodotriazole are described. Finally, for a series of crystals containing molecules with P=O groups, the presence of short X···O contacts (X = Cl, Br, I), which can be interpreted as halogen bonds, has been established with the help of X-ray analysis and quantum-chemical calculations [54][55][56][57][58][59][60][61]. Many other examples of XBs with phosphine oxides and related compounds can be found in CCDC data, which allowed us to perform an extensive database search and analyze the distributions of geometric parameters, as described in Section 4.…”