Synthesis and Cytotoxic Analysis of Novel Myrtenyl Grafted Pseudo-Peptides Revealed Potential Candidates for Anticancer Therapy.

Myrtenal is a natural monoterpene isolated from essential oils of several plants and their derivates have shown to have several biological properties including cytotoxicity. The cytotoxic activity of these derivates are being investigated for their antitumor effect leading to the development of potential anticancer agents. In this study, novels Myrtenyl grafted pseudo-peptides were designed, synthesized and functionally characterized as possible therapeutic agents for cancer treatment.

New anionic cobalt complexes using highly hindered bis-amides with varying donor abilities as ligands.

Four potential tetradentate ligands of formulae 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)ethane (H(4)L(1), 1), 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)propane (H(4)L(2), 2), 1,2-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)benzene (H(4)L(3), 3) and 1,8-bis-(3,5-di-tert-butyl-2-hydroxybenzamido)naphthalene (H(4)L(4), 4) have been prepared and the crystal structures of three of them (1, 3 and 4) determined by single crystal X-ray diffraction. The investigation of their complexing ability toward Co(II) afforded the compounds of formulae [Co(III)(L(3))Na(I)(H(2)O)(2)] (5), [Co(III)(L(n))Li(I)(H(2)O)2] with n = 1 (6), 2 (7) and 3 (8) and [Co(II)(L(4))Li(I)(2)] (9). Complexes 5-8 are square planar Co(III) species, as corroborated by the crystal structure of 5.

A unique tautomer of 1-n-hexyl-3-phenyl-1H-pyrazol-5-ol.

In the title compound, C15H20N2O, the bond distances and angles are consistent with the presence of the hydroxy tautomer. This tautomer was unambiguously determined by the clear presence of a H atom bonded to oxygen, as well as the total absence of any residual electron density around the N atom in the heterocycle, thus precluding any possibility of desmotropism.

An oximino tautomer of 1-n-decyl-4-hydroxyimino-3-methyl-1H-pyrazol-5(4H)-one.

The title compound, C14H25N3O2, consists of a five-membered heterocyclic ring to which a pendant decyl group is attached. The oximino tautomeric character of the molecule is clearly defined by the distribution of well defined double bonds in the heterocycle region (one C=O and two C=N). The most conspicuous packing interaction is the strong intermolecular hydrogen bond linking the oximino OH group and the carbonyl O atom to define broad planar hydrophilic strips running along the unique b axis.

Bis{1-n-hexyl-3-methyl-4-[1-(phenylimino)propyl]-1H-pyrazol-5-olato}copper(II): a new copper(II) complex with a chelating alkylpyrazolone-based enamine.

The title compound, [Cu(C19H26N3O)2], is the first reported complex of the alkylpyrazolone-derived ligand 1-n-hexyl-3-methyl-4-[1-(phenylimino)propyl]-1H-pyrazol-5(4H)-one. The most notable feature is the imine-enol character presented by the ligand due to coordination, in spite of its enamine-ketone structure in the free state. The ligand chelates through N and O atoms, resulting in a square-planar coordination around the CuII atom, which lies on an inversion centre.

Two enamines derived from 1-n-alkyl-3-methylpyrazol-5-ones.

The first two crystal structures of enamines derived from 1-n-alkyl-3-methyl-5-pyrazolones, namely 1-(n-hexyl)-3-methyl-4-[1-(phenylamino)propylidene]-2-pyrazolin-5-one, C19H27N3O, (I), and N,N'-bis[1-[1-(n-hexyl)-3-methyl-5-oxo-2-pyrazolin-4-ylidene]ethyl]hexane-1,6-diamine, C30H52N6O2, (II), are reported. The molecule of (II) lies about an inversion centre. Both (I) and (II) are stabilized by intramolecular N-H.