Organometallic-cyclodextrin inclusion compounds were obtained by the treatment of molybdenocene dichloride (Cp 2 MoCl 2 ) with the modified cyclodextrins (CDs) heptakis-2,3,6-tri-O-methyl-b-CD (TRIMEB) and 2-hydroxypropyl-b-CD (HPbCD) in aqueous solution. The products were isolated by liophilisation and characterised in the solid-state by powder XRD, thermogravimetric analysis, Raman and FTIR spectroscopy, and 13 C CP MAS NMR spectroscopy. The results are consistent with inclusion of Cp 2 MoCl 2 , rather than hydrolysis products such as [Cp 2 Mo(H 2 O)X] + (X = Cl, OH) or [Cp 2 Mo(H 2 O) 2 ] 2+ . The pure non-included metallocene Cp 2 MoCl 2 and its inclusion compounds with unmodified b-CD, TRIMEB and HPbCD were screened for their potential antiproliferative and cytotoxic activity, in both human cancer and healthy cell lines. Inclusion in CD was found to enhance the cytotoxic effect of Cp 2 MoCl 2 , with the TRIMEB adduct displaying the highest anti-tumour activity, along with the lowest toxicity towards non-neoplastic cells.

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A conformational analysis of ethyl 3-(3,4,5-trihydroxyphenyl)-2-propenoate (ethyl 3,4,5-trihydroxycinnamate, ETHPPE), a polyphenolic cinnamic ester which displays antiproliferative activity towards human adenocarcinoma cells, was carried out by Raman spectroscopy coupled to ab initio MO calculations. Apart from the optimised geometrical parameters for the most stable conformations of this compound (both for the trans and cis isomers), the corresponding harmonic vibrational frequencies were obtained. Eighteen distinct geometries were found, 12 for the lowest energy trans isomer and six for the cis species. The conformational preferences of this system were verified to be mainly ruled by the stabilising effect of p-electron delocalisation, a planar geometry being favoured. The orientation of the ester moiety showed to be the most determinant factor for the overall stability of the molecule. In the light of these results, a complete assignment of the corresponding Raman pattern was performed.

Trihydroxycinnamic derivatives were synthesized and evaluated for their antioxidant and cytotoxic activities. The ester derivatives exhibited a higher radical-scavenging activity, when liposomes were used as target systems, a fact which may be related to their lipophilicity and conformational preferences. These compounds were found to display significant growth inhibition and cytotoxic effects towards a human cervix adenocarcinoma cell line (HeLa). The partition coefficients presently obtained for the trihydroxycinnamic derivatives correlate well both with their structural characteristics and with their antioxidant/cytotoxic activities. A positive structure-activity-property relationship between cytotoxic and antioxidant activities, which is intrinsically related with physico-chemical and conformational properties, is anticipated, as a noteworthy study that must be done for phenolic systems. As damage events are frequently correlated with oxidative stress, the prevalence of both properties in a single compound could be beneficial in terms of rationale preventive or therapeutic purposes.