Zoila Gándara

An application of two MIFs-based tools (Volsurf+ and Pentacle) to binary QSAR: the case of a palinurin-related data set of non-ATP competitive glycogen synthase kinase 3β (GSK-3β) inhibitors.

VolSurf+ and GRIND descriptors extract the information present in MIFs calculated by GRID: the first are simpler to interpret and generally applied to ADME-Tox topics, whereas the latter are more sophisticated and thus more suited for pharmacodynamics events. Here we present a study which compares binary QSAR models obtained with VolSurf+ descriptors and GRIND for a data set of non-ATP competitive GSK-3β inhibitors chemically related to palinurin for which the biological activity is expressed in binary format. Results suggest not only that the simpler Volsurf+ descriptors are good enough to predict and chemically interpret the investigated phenomenon but also a bioactive conformation of palinurin which may guide future design of ATP non-competitive GSK-3 inhibitors.

[3,3]-Sigmatropic rearrangement mediated synthesis of chiral building blocks for the preparation of Gemini and its analogs

A novel synthetic methodology for the preparation of Gemini vitamin D3 analogs has been developed. Our procedure uses a key sigmatropic rearrangement which allows control over the C-20 stereochemistry, providing a versatile method to introduce novel side-chains to the vitamin D scaffold giving access to new analogs with potentially interesting biological properties.

Gemini Analogs of Vitamin D

The Gemini analogs are the last significant contribution to the family of vitamin D derivatives in medicine, for the treatment of cancer. The first Gemini analog was characterized by two symmetric side chains at C-20. Following numerous modifications, the most active analog bears a C-23-triple bond, C-26, 27- hexafluoro substituents on one side chain and a terminal trideuteromethylhydroxy group on the other side chain. This progression was possible due to improvements in the synthetic methods for the preparation of these derivatives, which allowed for increasing molecular complexity and complete diastereoselective control at C-20 and the substituted sidechains.

Synthesis and biological evaluation of a new vitamin D2 analogue

A new vitamin D(2) analogue was synthesized using the Julia-Kocienski olefination. It has antiproliferative effects on cell lines from squamous cell carcinomas of colon and head and neck, but is also as hypercalcaemic as calcitriol in vivo.

Structure-activity relationship study of vitamin D analogs with oxolane group in their side chain.

Synthetic analogs of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) have been developed with the goal of improving the biological profile of the natural hormone for therapeutic applications. Derivatives of 1,25(OH)2D3 with the oxolane moiety branched in the side chain at carbon C20, act as Vitamin D nuclear Receptor (VDR) superagonists being several orders of magnitude more active than the natural ligand. Here, we describe the synthesis and biological evaluation of three diastereoisomers of (1S, 3R)-Dihydroxy-(20S)-[(2″-hydroxy-2″-propyl)-tetrahydrofuryl]-22,23,24,25,26,27-hexanor-1α-hydroxyvitamin D3, with different stereochemistry at positions C2 and C5 of the oxolane ring branched at carbon C22 (1, C2RC5S; 2, C2SC5R; 3, C2SC5S). These compounds act as weak VDR agonist in transcriptional assays with compound 3 being the most active. X-ray crystallographic analysis of the VDR ligand-binding domain accommodating the three compounds indicates that the oxolane group branched at carbon C22 is not constrained as in case of compound with oxolane group branched at C20 leading to the loss of interactions of the triene group and increased flexibility of the C/D-rings and of the side chain.