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The natural abundance (2)H NMR characterization of raspberry ketone 1 extracted from himalayan Taxus baccata and of the accompanying (R) carbinol 2 is performed and compared with that of samples of 1 obtained from 2 by oxidation with Candida boidinii and CrO(3), respectively. The determination of the delta((13)C) and/or delta((18)O) values of the above extractive products and of benzoic acid (6) and 4-butylphenol (10), obtained from natural of synthetic 1, and of 4-phenylbutan-2-ol (8), prepared from extractive 2, allows a description of the labeling pattern of this set of products. A graph of (D/H)(3)/(D/H)(2) vs (D/H)(5)/(D/H)(4) (Figure 3) of the presently examined samples and of those previously characterized in the laboratory, including three commercial samples sold as natural, defines three areas, containing (a) the material of botanical origin and that produced from extractive 2 by biooxidation, (b) those produced by bioreduction of the unsaturated ketone 3, and (c) the synthetic samples.

In this work we synthesized new MDI–-based poly(ether)urethanes (PEUs) with phospholipid-like residue as chain extender. Polymers were prepared by a conventional two-step solution polymerization procedure using 4,4'-diphenylmethanediisocyanate (MDI) and poly(1, 4-butanediol) with 1000 as molecular weight to form prepolymers which were successively polymerized with 1-glycerophosphorylcholine (1-GPC), 2-glycerophosphorylcholine (2-GPC) or glycerophosphorylserine (GPS) as chain extenders. Two reference polymers bearing 1,4-butandiol (BD) have been also synthesized. The polymers obtained were characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and modulated scanning calorimetry (MDSC). The biocompatibility of synthesized segmented polyurethanes was then investigated by platelet-rich plasma contact studies and related scanning electron microscopy (SEM) photographs for blood compatibility and cytotoxicity assay (MTT test) on material elution to assess the effect of any toxic leachables on cellular viability. Three polymers among all have given very satisfactory results suggesting to investigate more deeply their possible use in biomedical devices.