Chelating Phosphine–N-Heterocyclic Carbene Platinum Complexes via Catalytic Asymmetric Hydrophosphination and Their Cytotoxicity Toward MKN74 and MCF7 Cancer Cell Lines

Abstract

A series of activated vinyl azoles was hydrophosphinated in the presence of a chiral palladacycle catalyst under mild conditions to give enantioenriched phosphine azoles with moderate enantioselectivities and yields. The racemic phosphine azoles were transformed into eleven novel chelating phosphine–N-heterocyclic carbene (NHC) platinum complexes. The drug efficacies of nine selected phosphine–NHC platinum­(II) chlorides in two cancer cell lines (MKN74 and MCF7) were evaluated, and two were found to exhibit activities comparable to that of cisplatin.

Experimental and computational tuning of metalla-N-heterocyclic carbenes at palladium(ii) and platinum(ii) centers

“…3 e ,24 The Pt–C carbene distances 1.983(6)–1.989(5) Å are slightly smaller than those of typical Pt–C bonds (1.995–2.023 Å) 5 d ,25 reported for the relevant Pt II –ADC complexes and are close to the Pt–C distances in Pt–NHC complexes (1.970–1.991 Å). 26 On the other hand, the Pt–C bond lengths are sufficiently larger than those in Pt–NHCs, where the NHC is included in the extended rigid π-system (1.906–1.970 Å) 27 and in Pt–CAAC complexes (1.942–1.967 Å). 28 The bond lengths in the first carbene moiety C 1 –N 1 (1.349(8) Å) and C 1 –N 3 (1.341(7) Å) are similar and are between a single CN bond ( e.g.…”

Asymmetric addition of P-H compounds to unsaturated carbonyl derivatives

“…29,40 Catalyst 28 was used to form biologically-active chiral Pt complexes. 41 After it was used in the addition of diphenyl phosphane (17) to N-vinylbenzimidazoles, the adducts obtained were converted into new Pt complexes, the cytotoxicity of which toward cancer cell lines was investigated.…”