17537-28-9Relevant articles and documents
Electrospray ionization tandem mass spectrometry of monoketone curcuminoids
Vieira, Tatiana M.,Orenha, Renato P.,Crevelin, Eduardo J.,Furtado, Saulo S.P.,Vessecchi, Ricardo,Parreira, Renato L.T.,Crotti, Ant?nio E.M.
, (2020)
Rationale: Although monoketone curcuminoids (MKCs) have been largely investigated due to their biological activities, data on the gas-phase fragmentation reactions of protonated MKCs under collision-induced dissociation (CID) conditions are still scarce. Here, we combined electrospray ionization tandem mass spectrometry (ESI-MS/MS) data, multiple-stage mass spectrometry (MSn), deuterium exchange experiments, accurate-mass data, and thermochemical data estimated by computational chemistry to elucidate and to rationalize the fragmentation pathways of eleven synthetic MKCs. Methods: The MKCs were synthesized by Claisen-Schmidt condensation under basic (1–9) or acidic (10–11) conditions. ESI-CID-MS/MS analyses and deuterium-exchange experiments were carried out on a triple quadrupole mass spectrometer. MSn analyses on an ion trap mass spectrometer helped to elucidate the fragmentation pathways. Accurate-mass data and thermochemical data, obtained at the B3LYP/6–31+G(d,p) level of theory, were used to support the ion structures. Results: The most intense product ions were the benzyl ions ([C7H2R1R2R3R4R5]+) and the acylium ions ([M + H ? C8H3R1R2R3R4R5]+), which originated directly from the precursor ion as a result of two competitive hydrogen rearrangements. Product ions [M + H – H2O]+ and [M + H ? C6HR1R2R3R4R5]+, which are formed after Nazarov cyclization, were also common to all the analyzed compounds. In addition, ?Br and ?Cl eliminations were diagnostic for the presence of these halogen atoms at the aromatic ring, whereas ?CH3 eliminations were useful to identify the methyl and methoxy groups attached to this same ring. Nazarov cyclization in the gas phase occurred for all the investigated MKCs and did not depend on the presence of the hydroxyl group at the aromatic ring. However, the presence and the position of a hydroxyl group at the aromatic rings played a key role in the Nazarov cyclization mechanism. Conclusions: Our results reinforce some aspects of the fragmentation pathways previously published for 1,5-bis-(2-methoxyphenyl)-1,4-pentadien-3-one and 1,5-bis-(2-hydroxyphenyl)-1,4-pentadien-3-one. The alternative fragmentation mechanism proposed herein can explain the fragmentation of a wider diversity of monoketone curcuminoids.
New thiazolopyrimidine as anticancer agents: Synthesis, biological evaluation, DNA binding, molecular modeling and ADMET study
Al-Rashood, Sara T.,Elshahawy, Shymaa S.,El-Qaias, Asmaa M.,El-Behedy, Dina S.,Hassanin, Alshaimaa A.,El-Sayed, Selwan M.,El-Messery, Shahenda M.,Shaldam, Moataz A.,Hassan, Ghada S.
, (2020)
In the present study, new series of thiazolopyrimidine derivatives was synthesized as purine analogs. The structures of the products were confirmed through spectroscopic techniques such as NMR and mass spectrometry. In addition, the synthesized compounds
Synthesis, characterization and antichagasic evaluation of thiosemicarbazones prepared from chalcones and dibenzalacetones
da Silva, Aline Alves,Maia, Pedro Ivo da Silva,Lopes, Carla Duque,de Albuquerque, Sergio,Valle, Marcelo Siqueira
, (2021/02/12)
Chagas disease is a neglected disease, being one of the leading causes of death from infectious diseases. In view of the severity of this pathology, this work describes the synthesis of new thiosemicarbazones derived from chalcones and dibenzalacetones as potential drugs for the treatment of this disease. The structures of all compounds were elucidated by infrared (IR) and nuclear magnetic resonance (1H and 13C NMR) spectroscopies. The chalcone derived thiosemicarbazones 10-14 were tested against the intracellular amastigote form of the protozoan Trypanosoma cruzi and had their cytotoxicity assessed using LLC-MK2 cells. The compound 10 (IC50 = 12.25 μM) presented the best activity when compared with the standard drug benznidazole (IC50 = 5.64 μM).
Synthesis and assessment of the antioxidant and antitumor properties of asymmetric curcumin analogues
Li, Qingyong,Chen, Jian,Luo, Shuyue,Xu, Jialin,Huang, Qiaoxian,Liu, Tianyu
, p. 461 - 469 (2015/03/04)
In this study, 12 asymmetric curcumin (CUR) analogues and 5 symmetric curcumin derivatives were synthesized, the antioxidant activity of these derivatives were evaluated by radicals 1,1-diphenyl-2- picryl-hydrazyl (DPPH) assay, 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay, ROO. (TRAP) assay and O2-. (NET) assay and anti-proliferative activities of these analogues were assessed against the human hepatoma cell line (SMMC-7721), the human breast cancer cell line (MCF-7) and the human prostate cancer cell lines (PC-3). Most of the asymmetric compounds showed stronger antioxidant activities than Vitamin C (Vc). Curcumin analogues reducing free radicals contain two reaction mechanisms: H-atom and electron transfer mechanisms. Compound 14 showed the most significant antioxidant activity compared with curcumin and other derivatives. Shorted the carbon chain of 14 can reduce the OeH bond dissociation enthalpy (BED) to improve the antioxidant activity. The antioxidant activity of 25 was similar to curcumin. All of the compounds performed better in an anti-proliferate assay than curcumin, especially compound 25, which exhibited the preferential cytotoxic activity against MCF- 7 cells(25, IC50 = 9.11 μM, curcumin, IC50 = 70.2 μM). Considering these data, future studies should be performed to assess the therapeutic values of these asymmetric curcumin analogues.
