Search For Cytotoxic Compounds Research Articles

Search for cytotoxic compounds against ovarian cancer cells: Synthesis, characterization and assessment of the activity of new camphor carboxylate and camphor carboxamide silver complexes

Five silver camphor complexes of formulae [Ag2(L)(L′)2] (1,3,5) or [Ag(L)2(L′)] (2,4) were synthesized from silver nitrate and the suitable camphor carboxylate (L1) or camphor carboxamides (L3, L4). The complexes were characterized by elemental analysis and spectroscopic techniques (NMR, FTIR, XPS). Computational calculations support coordination of the carboxylate group to silver, in the case of complex 2 and combined mixed keto/carboxylate in the case of complex 1. The stability of the complexes highly relies on the tetrahedral geometry of the lithium ion that binds to four oxygen atoms of the camphor carboxylate ligands. The redox properties of complexes 1 and 4 studied by cyclic voltammetry confirm the facile reduction of the metal sites that depending on the experimental conditions may lead to formation of silver nanoparticles as confirmed by XPS and TEM. Complexes 1, 2 and 4 were tested for cytotoxic activities against A2780 (IC50, 11–14 μM) and A2780 cisplatin resistant (A2780cisR) (IC50, 4–7 μM) cells using the MTT assay. The result showed that the complexes have anticancer activity higher than cisplatin. Complex 1 was also probed for cytotoxicity against the non-tumoral human embryonic kidney (HEK 293, IC50, 62.2 ± 16 μM) cells showing low toxicity in agreement with the silver camphor carboxylate complexes having a considerable selectivity for the ovarian cancer cells A2780 and cisplatin resistant A2780cisR which is a key point under pharmacological uses.

Cytotoxic Activity of Dihydrochalcones Isolated from Corema Album Leaves against HT-29 Colon Cancer Cells

During our search for cytotoxic compounds from Andalusian vascular plants, the ethyl acetate extract from the leaves of Corema album (L.) D. Don (Ericaceae) was selected for its cytotoxic activity against the HT-29 human colon adenocarcinoma cell line. Two dihydrochalcones, 2',4'-dihydroxydihydrochalcone (1) and 2'-methoxy-4'-hydroxydihydrochalcone (2), have been isolated from the leaves of C. album. Their structural identification was based on 1H NMR and 13C NMR data, including 2D NMR, and mass spectrometry. These compounds were subjected to the sulfhorhodamine B (SRB) cytotoxic assay against human colon adenocarcinoma cells (HT-29). Compounds 1 and 2 showed higher cytotoxicity than the positive control 5-fluorouracil (5-FU); the IC50 values (microM +/- SEM) were 1.8 +/- 0.4 for compound 1, 8.5 +/- 2.1 microM for compound 2, and 8.7 +/- 4.0 for 5-FU. The cytotoxic activity of 1 and 2 was reduced in the presence of the antioxidants N-acetylcysteine (NAC) and Mn(III) Tetrakis(1-methyl-4-pyridyl) porphyrin pentachloride (MnTMPyP), therefore suggesting that reactive oxygen species generation participates in the cytotoxic activity of these dihydrochalcones.

Cholestane glycosides from the bulbs of Galtonia candicans and their cytotoxicity.

Further search for cytotoxic compounds contained in the bulbs of Galtonia candicans (Liliaceae) led to the isolation of four potent cytotoxic cholestane glycosides (1-4) based upon 3beta,16beta,17alpha-trihydroxycholest-5-en-22-one, three of which (2-4) have not been reported previously. A new cholestane bisdesmoside (5) and a new rearranged cholestane glycoside (6) were also isolated. The structural assignment of the new constituents was carried out by spectroscopic analysis and a few chemical transformations.

ChemInform Abstract: Biologically Active Compounds from Marine Organisms

In our search for cytotoxic compounds from marine animals we have isolated representatives from various classes of nitrogen-containing compounds, most of which show cytotoxic activity. Structure elucidation of these compounds is discussed. Included among the isolates are new acylated spermidines, polycyclic aromatic alkaloids related to amphimedine and 2-bromoleptoclinidinone, and a representative of a novel sulfur containing 3,5,8-isoquinolinetrione.

Biologically active compounds from marine organisms

Abstract