Tethering Carbohydrates to the Vinyliminium Ligand of Antiproliferative Organometallic Diiron Complexes

Abstract

Four propargyl O -glycosides derivatized with mannose, glucose, and fructose moieties were synthesized and then incorporated within a diiron structure as part of a vinyliminium ligand. Hence, six glycoconjugated diiron complexes, [ 2–5 ]CF 3 SO 3 (see Scheme 1) and the nonglycosylated analogues [ 6a–b ]CF 3 SO 3 , were obtained in high yields and unambiguously characterized by elemental analysis, mass spectrometry, and IR and multinuclear NMR spectroscopies. All compounds exhibited a significant stability in DMSO- d 6 /D 2 O solution, with 63–89% of the complexes unaltered after 72 h at 37 °C and also in the cell culture medium. The cytotoxicity of [ 2 – 6 ]CF 3 SO 3 , as well as that of previously reported 7 and 8 , was assessed on CT26 (mouse colon carcinoma), U87 (human glioblastoma), MCF-7 (human breast adenocarcinoma), and RPE-1 (human normal retina pigmented epithelium) cell lines. In general, the IC 50 values correlate with the hydrophobicity of the compounds (measured as octanol–water partition coefficients) and do not show an appreciable level of selectivity against cancer cells with respect to the nontumor ones.

Adding Diversity to Diiron Aminocarbyne Complexes with Amine Ligands

“…We hypothesize that the two species correspond to the cis form (the chemical shift values of the Cp rings strictly match those related to the cis isomer of 2a), existing as two diastereoisomers due to the chirality of the diiron core associated with the presence of a stereocenter on the five-membered carbamate cycle. A similar feature was previously observed upon tethering enantiopure sugar scaffolds to a vinyliminium ligand bridging coordinated to the [Fe 2 Cp 2 (CO) 2 ] core [66].…”

When ferrocene and diiron organometallics meet: triiron vinyliminium complexes exhibit strong cytotoxicity and cancer cell selectivity

“…23 Complexes of type IV permit one to have a vast choice of substituents, 25 including the incorporation of bioactive groups regulating the cytotoxic activity. 26 Different mechanisms, mainly ROS production but also protein interaction and weak DNA binding, may contribute to the mode of action of III and IV .…”

[Fp(CH4)]+, [η5-CpRu(CO)2(CH4)]+, and [η5-CpOs(CO)2(CH4)]+: A Complete Set of Group 8 Metal–Methane Complexes

“…Cyclopentadienyliron dicarbonyl dimer, [η 5 -CpFe­(CO) 2 ] 2 , and its derivatives that contain the [η 5 -CpFe­(CO) 2 ] fragment commonly referred to as Fp (or fip) complexes (Figure ) are one of the archetypal classes of organometallic complexes and were first synthesized in the Wilkinson lab in the 1950s . This family of complexes has been the subject of intense investigation, − but reports on the analogous cyclopentadienyl ruthenium dicarbonyl (Rp) complexes are limited in comparison. − …”