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Titanium silicate molecular sieve, having MFI (TS-1) topology, efficiently catalyses the oxidative cleavage of various tosylhydrazones to the corresponding carbonyl compounds in moderate to good yields, using dilute hydrogen peroxide (30%) as an oxidising agent and involving a unique electrophilic species; mechanistically, the intermediacy of oxaziridine has been established.

The organic extract of the fermentation broth of an unidentified fungus was found to contain three epidermal growth factor (EGF) receptor anagonists: SCH 64874 ( 1 ), SCH 64875 ( 2 ), SCH 64877 ( 3 ). These compounds belong to a family of thiodiketopiperazine derivatives and are esters of an eight carbon aliphatic acid, 2,4- dimethyl-3-hydroxyhexanoic acid and a thiodiketopiperazine, aranotin. They exhibited potent EGF receptor antagonist activity. The IC 50 in EGF receptor assays for compounds 1 , 2 and 3 are 1.0, 1.0 and 1.25 μg/ml, respectively.

A novel secondary metabolite SCH 42282 (1), with antifungal activity was isolated from the fermentation broth of a soil actinomycete identified as a Microtetraspora sp. The active compound was separated from the fermentation broth by butanol extraction and purified on a silica gel column and by multi-coil counter current chromatography. The compound was identified as a novel macrolactam trisaccharide related to SCH 38518 (4). The structure was established by hydrolysis of the parent compound and spectroscopic studies of the acetate derivative. The compound is active against Candida spp. (Geometric Mean MIC's. 18 micrograms/ml) but less active SCH 42729 (3). the disaccharide (Geometric Mean MIC's, > or = 10.7 micrograms/ml and SCH 38518 (4), the monosaccharide (Geometric Mean Mic's, 3.8 micrograms/ml.

The 70% aqueous methanolic extract of the Chinese plant Aristolochia manshuriensis was found to contain two novel substituted phenanthrene compounds, SCH 546909 ( 1 ), and another phenanthrene glycoside ( 2 ). The structures of 1 and 2 were established based on NMR studies. They were identified as inhibitors of the CDK2 enzyme. Compound 1 was found to be a potent inhibitor of the CDK2 enzyme with an IC 50 of 140 nM, whereas compound 2 was found to be less active with an IC 50 of >10 μM.

A convenient preparation of (1′R,2′S,3′R,4′S)-1-(2′,3′4′-trihydroxycyclopent-1′-yl)-1H-uracil (carbocyclic 5′-noruridine, 1) is described in 2 steps from the palladium complex of (+)-(1R,4S)-4-hydroxy-2-cyclopenten-1-yl acetate (3) and the sodium salt of uracil (2). Compound 1 was sought as a previously unknown member of the series of carbocyclic 5′-nor nucleosides needed as moieties for new oligomers. With 1 available, its antiviral properties and those of its enantiomer (5) are reported with 5 showing promising activity towards Epstein-Barr virus.

5′-Nor carbocyclic nucleosides have been found to possess a variety of meaningful biological properties. One of the building blocks for this class of compounds is (1S,2R,3S,4R)-4-aminocyclopentane-1,2,3-triol. To date, the reported routes to this compound are not particularly facile. Thus, a convenient route to this triol in its protected isopropylidene form (2) from (+)-(1R,4S)-4-hydroxy-2-cyclopenten-1-yl acetate. This will facilitate the preparation of new 5′-nor carbocyclic nucleosides in the “D-ribo-like” configuration. This method is also adaptable to the “L-like” series and the 2′- and 3′-deoxy analogs.

The 70% aqueous methanol extract of the Peruvian plant Lippia alva (Verbenaceae) was found to contain three novel compounds, 1, 2, and 3, which were identified as inhibitors of the chemokine receptor CCR5. The structures of 1-3 were established based on extensive NMR studies. Compounds 1-3 inhibited CCR5 receptor signaling as measured by a calcium mobilization assay with IC(50) values of 5.5, 6.0, and 7.2 microg/mL, respectively.

The 70% aq methanolic extract of the Peruvian plant Stylogne cauliflora was found to contain two novel oligophenolic compounds SCH 644343 (1) and SCH 644342 (2), which were identified as inhibitors of HCV NS3 protease. The structure of 1 and 2 was established based on high-resolution NMR studies. Compound 1 inhibited HCV NS3 protease with an IC(50) of 0.3 microM, while compound 2 showed an IC(50) of 0.8 microM.

The aqueous methanolic extract of a sea cucumber was found to contain two triterpene glycosides 1 and 2. The structures of 1 and 2 were established based on high-resolution NMR studies. Compounds 1 and 2 exhibited inhibitory activity (K(i)) of 30 and 5microM, respectively, in a chemokine receptor subtype 5 (CCR5) assay. Both compounds did not show any significant inhibition in a CXCR2 assay at 50microM, suggesting their selectivity for the CCR5 receptor.

A preparation of (1′R,2′S,3′R,4′S)-1-(2′,3′,4′-trihydroxycyclopent-1′-yl)-lH-cytosine (5′-norcarbodine, 3) has formally been achieved in 2 steps from (+)-(1R,4S)-4-hydroxy-2-cyclopenten-1-yl acetate (4) and cytosine. The L-like enantiomer of 3 (that is, 6) is also reported using the enantiomer of 4 (that is, 7). In evalu ating 3 and 6 for antiviral potential against a number of viruses, compound 3 was found to have activity towards Epstein-Barr virus (EBV).