The title compound has been synthesised in racemic form by a biomimetic reaction sequence. The two enantiomers were resolved by column chromatography of one of the synthetic intermediates. On the basis of CD results a tentative absolute configuration for the synthetic enantiomers and natural 3',4-di-0methylcedrusin is proposed.Sungre de drug0 (dragon's blood), a blood-red latex produced by various South American Croton species, is widely used in local medicine for its wound-healing properties and as an anticancer agent . 3',4-Di-0-methylcedrusin or 3-[2-( 3,4-dimethoxyphenyl)-3-hydroxymethyl-7-methoxy-2,3-dihydro-1 -benzofuran-5-yl]propan-l-015 has been shown to be one of the active principles being a wound healing agent and an inhibitor of thymidine incorporation in endothelial cells. p 2 Results and discussionRacemic 5 has been synthesised as shown in Scheme 1. Near quantitative esterification of ferulic acid was achieved with a heterogeneous polymer catalyst to give methyl ferulate 1 the biomimetic 6,7 oxidative coupling of which, in the presence of silver oxide,8 to generate the dihydrobenzofuran skeleton is the crucial step in the reaction sequence. Compound 2, shown unequivocally by X-ray crystallography to have a transconfiguration,' upon attempted methylation with diazomethane or with dimethyl sulfate gave complex mixtures of unidentified compounds. With methyl iodide, however, it gave compound 3, although to avoid the formation of, for instance, C-methylated side products (the formation of a product with a molecular weight of 442 has been demonstrated by DCI-mass spectrometry) the reaction time has to be kept relatively short; this results in relatively low product yields. Hydrogenation of the double bond of 3 in the presence of Pd-C yields compound 4 almost quantitatively, although, prolonged reaction times or large amounts of catalyst have to be avoided, since they result in ring opening of the dihydrofuran ring. LiAlH, reduction of both ester functions of 4 gave 3',4-di-O-methylcedrusin 5.The structures of compounds 2 to 5 were established on the basis of 'H NMR-, 13C NMR-, COSY, and HETCOR-spectral evidence (Tables 1 and 2). Both natural 3',4-di-O-rnethylcedrusin and the racemic ' F1 m id 2: -I XI 9

The adducts of phenylglycidyl ether with 2'-deoxyadenosine (dAdo) and 2'-deoxycytidine (dCyd) exhibit structural modifications. The N-1 adduct of dAdo underwent rearrangement to the N-6 adduct; the N-3 adduct of dCyd was deaminated to the corresponding 2'-deoxyuridine adduct. These structural modifications were studied by using liquid chromatography-electrospray tandem mass spectrometry, and kinetic data for both reactions are presented. The low energy (+) collision-activated dissociation spectra of the dAdo adducts allow the two positional isomers N-1 versus N-6 to be distinguished. The structure of the latter is independently proven by an extended NMR study. For the dCyd and 2'-deoxyuridine adducts, information about the alkylation site is found in the (-) collision-activated dissociation spectra. These spectra show the presence of an unexpected N-4-alkylated dCyd in addition to the two epimeric N-3 adducts.

An approach to identify β-secretase 1 (BACE1) fragment binders that do not interact with the catalytic aspartate dyad is presented. A ThermoFluor (thermal shift) and a fluorescence resonance energy transfer enzymatic screen on the soluble domain of BACE1, together with a surface plasmon resonance (SPR) screen on the soluble domain of BACE1 and a mutant of one catalytic Asp (D32N), were run in parallel. Fragments that were active in at least two of these assays were further confirmed using one-dimensional NMR (WaterLOGSY) and SPR binding competition studies with peptidic inhibitor OM99-2. Protein-observed NMR (two-dimensional 15N heteronuclear single-quantum coherence spectroscopy) and crystallographic studies with the soluble domain of BACE1 identified a unique and novel binding mode for compound 12, a fragment that still occupies the active site while not making any interactions with catalytic Asps. This novel approach of combining orthogonal fragment screening techniques, for both wild-type and mutant enzymes, as well as binding competition studies could be generalized to other targets to overcome undesired interaction motifs and as a hit-generation approach in highly constrained intellectual property space.

In search for new compounds with potential for clinical use as antifungal agents in dermatology, a series of 12 azole compounds were synthesized stereospecifically and investigated specifically for their activity against dermatophyte fungal infections in animal models. This panel of azoles was studied in vitro and compared with itraconazole and terbinafine for their antifungal activity using a panel of 24 Candida spp. and 182 dermatophyte isolates. Three azoles (1c, 2c, and 4c) showed in vitro antifungal potency equivalent to itraconazole, but superior to terbinafine, against a panel of 24 Candida spp. with comparable or lower activity than that of itraconazole and terbinafine against 182 dermatophyte isolates and only rare activity against other pathogenic fungi. However, in vivo 1c and 4c, both given orally, demonstrated antifungal activity at least three times greater than itraconazole and were superior compared to terbinafine in M. canis infected guinea pigs. In a mouse model infected by T. mentagrophytes, again 4c, but not 1c, showed 5-fold superior activity over itraconazole and terbinafine. Compound 2c was effective in both models but less effective than itraconazole in these models. On the basis of these promising results, 4c is currently being clinically investigated for its potential as a novel antifungal agent against dermatophytosis.

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