Corrigendum to "Synthesis and Characterization of New Palladium(II) Thiosemicarbazone Complexes and Their Cytotoxic Activity against Various Human Tumor Cell Lines".

[This corrects the article DOI: 10.1155/2013/524701.].

Constituents of Corynaea crassa "Peruvian Viagra"

Abstract A phytochemical investigation of methanol and n-hexane extracts of tuber/roots of Corynaea crassa Hook. f., Balanophoraceae, led to the isolation and characterization of β-sitosterol, lupenone, β-amyrone, lupeol, and β-amyrine. Unusual complex 1:1 mixtures of lupenone/β-amyrone and lupeol/β-amyrine obtained from the extracts were identified by NMR and HR-MS experiments. The structure of the 1:1 lupenone/β-amyrone mixture was confirmed by X-ray analysis. These triterpene ketone derivatives, only distinguished either by 5- or 6-membered E ring, co-crystallize in one common unit cell in the solid state.

Synthesis and Characterization of New Palladium(II) Thiosemicarbazone Complexes and Their Cytotoxic Activity against Various Human Tumor Cell Lines.

The palladium(II) bis-chelate complexes of the type [Pd(TSC(1-5))2] (6-10), with their corresponding ligands 4-phenyl-1-(acetone)-thiosemicarbazone, HTSC(1) (1), 4-phenyl-1-(2'-chloro-benzaldehyde)-thiosemicarbazone, HTSC(2) (2), 4-phenyl-1-(3'-hydroxy-benzaldehyde)-thiosemicarbazone, HTSC(3) (3), 4-phenyl-1-(2'-naphthaldehyde)-thiosemicarbazone, HTSC(4) (4), and 4-phenyl-1-(1'-nitro-2'-naphthaldehyde)-thiosemicarbazone, HTSC(5) (5), were synthesized and characterized by elemental analysis and spectroscopic techniques (IR and (1)H- and (13)C-NMR). The molecular structure of HTSC(3), HTSC(4), and [Pd(TSC(1))2] (6) have been determined by single crystal X-ray crystallography. Complex 6 shows a square planar geometry with two deprotonated ligands coordinated to Pd(II) through the azomethine nitrogen and thione sulfur atoms in a cis arrangement. The in vitro cytotoxic activity measurements indicate that the palladium(II) complexes (IC50 = 0.01-9.87 µM) exhibited higher antiproliferative activity than their free ligands (IC50 = 23.48-70.86 and >250 µM) against different types of human tumor cell lines. Among all the studied palladium(II) complexes, the [Pd(TSC(3))2] (8) complex exhibited high antitumor activity on the DU145 prostate carcinoma and K562 chronic myelogenous leukemia cells, with low values of the inhibitory concentration (0.01 and 0.02 µM, resp.).