Nguyen Huu Dinh

Synthesis, structure, and in vitro cytotoxicity of organoplatinum(II) complexes containing aryl olefins and quinolines

Ten new organoplatinum(II) complexes, [PtCl(Saf)(8-OQ)] (1), [Pt(Saf-1H)(8-OQ)] (2), [PtCl(Meug)(8-OQ)] (3), [Pt(Meug-1H)(8-OQ)] (4), [PtCl(Meteug)(8-OQ)] (5), [PtCl(Meteug)(Q)] (6), [Pt(Meteug)(Q-COO)] (7), [Pt(Eteug-1H)(Q)] (8), [Pt(Eteug-1H)(8-OQ)] (9), and [Pt(Eteug-1H)(Q-COO)] (10) (where Saf = safrole, Meug = methyleugenol, Meteug = methyl eugenoxyacetate, Eteug = ethyl eugenoxyacetate, Q = quinoline, 8-OQ = 8-hydroxyquinolinate, and Q-COO = quinolin-2-carboxylate), were synthesized and characterized by spectroscopic methods. The position of N and O donors of quinoline ligands in comparison with the ethylenic double bond and the aromatic C5 of the aryl olefins in platinum(II) coordination sphere of 1–10 was determined using their NOESY spectra and confirmed by single-crystal X-ray diffraction of 10. Complexes 1, 2, 3, 4, and 9 exhibit impressive activities on four human cancer cell lines KB, Hep-G2, Lu, and MCF7 with IC50 = 1.4–9.6 μM. Complexes 1, 2, 4, and 9 gave better antitumor activity than cisplatin against examined cell lines. Graphical abstract

Synthesis and solution structures of some platinum(II) complexes containing chelating safrole and amine

Reaction of the dinuclear chelate ring complex [Pt2Cl2(Saf-1H)2], Saf-1H: deprotonated safrole, with various amines afforded cis-[Pt(Saf-1H)(Am)Cl], Am: NH3 (1), Me2NH (2), Et2NH (3), morpholine (4), cyclohexylamine (5), benzylamine (6), aniline (7), o-toluidine (8), m-toluidine (9), p-toluidine (10), pyridine (11), 2-aminopyridine (12), and quinoline (13). The 1H NMR and nuclear overhauser effect spectroscopy (NOESY) spectra of the reported complexes were accurately analyzed. NOESY spectra show that the complexes have a cis-configuration, in which the alkyl and aryl groups of coordinated amines are in proximity to the allyl group of chelating safrole. Complexes 11, 12, and 13 exhibit inhibitory activities on human cancer cells HepG2 and Lu with IC50 = 2.5–5.0 µg mL−1.

Mono- and dinuclear metallacyclic complexes of Pt(II) synthesized from some eugenol derivatives

The complexes K[PtCl3(Meug)] (1; Meug = methyleugenol), K[PtCl3(Meteug)] (2; Meteug = methyl eugenoxyacetate), and K[PtCl3(Eteug)] (3; Eteug = ethyl eugenoxyacetate) reacted with AgNO3, SnCl2, KOH, or ethanol–water solutions to lose one aryl proton and form dinuclear metallacyclic complexes Pt2Cl2(Meug-1H)2 (4), Pt2Cl2(Meteug-1H)2 (5), and Pt2Cl2(Eteug-1H)2 (6), respectively. Complexes 4–6 reacted with aliphatic, aromatic, and heterocyclic amines to give various mononuclear metallacyclic platinum complexes 7–15. 1H NMR spectra showed that in 4–15 Meug, Meteug, and Eteug are bound with Pt(II) both at the benzene carbon and at the ethylenic double bond of the side chain. NOESY spectra and single-crystal X-ray diffraction indicated that in 7–15 the amines are in cis-position with respect to the ethylenic double bond.

Synthesis and spectral characterization of platinum(II) complexes containing eugenol, a natural allylphenol

Abstract For the first time, eugenol, a natural bioactive allylphenol, was introduced into coordination with platinum(II) by replacement of ethylene from Zeise’s salt with eugenol (Eug). The obtained complex, K[PtCl3(Eug)] (1), was used as the key compound for preparation of the series of trans-[PtCl2(Eug)(Amine)] (2–11), [PtCl(Eug)(8-O-quinoline)] (12) and [PtCl(Eug)(2-O2C-quinoline)] (13). The synthesized complexes were characterized by elemental analyses, IR, 1H NMR, 13C NMR, HSQS, HMBC, NOESY, and MS spectra. In 1–13 eugenol coordinates with Pt(II) at ethylenic double bond of the allyl group, the donor N of the amines is in trans-position in comparison with the double bond. A display of the trans-effect on the chemical shift of 1H and 13C was remarked. Seven complexes were tested for cell in vitro cytotoxicity on human cancer cells. Complexes 3 and 12 exhibit high activities on Hep-G2 with IC50 = 3.12 and 5.29 μM; 12 gives high activity against KB, Lu and MCF-7 with IC50 = 0.43, 2.95 and 1.84 μM, respectively. Most of these IC50 are lower than those of cisplatin.

Aci-Quinone Compounds from Eugenoxyacetic Acid and Methyleugenol: Preparation and Reaction

A new aci-quinone compound, 4-(aci-nitro)-2-(methoxy)-5-(3-nitro-2-(nitrooxy)propyl)-cyclohexa-2,5dienone (2), an analog to 4-(aci-nitro)-2-(carboxymethoxy)-5-(3-nitro-2-(nitrooxy)propyl)-cyclohexa-2,5-dienone (1), was successfully synthesized and fully characterized by spectroscopic methods. The reactions of 1 and 2 with various reagents such as hydroxylamine, acetic anhydride, semicarbazide and thiosemicarbazide were examined. The structure of 11 obtained new compounds was established by IR, H NMR, C NMR, HMBC and MS spectra. It was shown that the unstable, sensitive aci-quinone structure of compounds 1 and 2 can exist in anhydrous organic solvents such as AcOEt, EtOH but in the presence of water, H, HO or at high temperatures, the aci-quinone structure of both 1 and 2 tendentiously transformed into the more stable nitro-phenol form.

Contribution to syntheses of some azomethines of 5-amino-1-methyl-2-phenylindole series

Ten azomethines of 5-amino-1-methy-2-phenyllindole series have been synthesized by reaction between these amines and substituted benzaldehyde. The structures of obtained compounds have been confirmed by using spectroscopic methods, such as IR, mass, 1 H-NMR, 13 C-NMR spectra with two-dimensional experiments (HSQC and HMBC).