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(NH4)42 [MoVI72MoV60O372 (OAc)30(H2O)72] ·300H2O·10NH4OAc (I) is synthesized by addition of the oxalato complex (NH4)2 [Mo2O4(C2O4)2 (H2O)2]·3H2O to an aqueous solution of (NH4)6Mo7O24, AcOH, and NH4OH at pH 4 (4 h, 16% yield).

CYM 50333 (I) and CYM 50367 (II), novel selective S1P4 antagonists with activities in the nanomolar range, represent valuable small molecule tools to investigate the biological and pharmacological role of the target receptor in megakaryocyte differentiation and fundamental immune processes.

The structure, stereochemistry, solution conformation and nematocidal activity of Ophiobolin K (1a) and 6-epiophiobolin K (1b) isolated from Aspergillus ustus has been described. The molecular structure of these compounds were deduced from extensive use of 2D NMR spectroscopy. The stereochemistry and solution conformation was determined in CDCl3 by the application of extensive 1H-1H NOE difference spectroscopy. Significant difference in the conformation of A/B cis 1a and its A/B trans isomer 1b was observed including the folding of the side chain. Ophiobolin K showed a unique boat like conformation whereas the B ring of 6- epiophiobolin K must exist in at least two different conformations. Ophiobolin K exhibited nematocidal activity (ED50 10 μg/mL) against the free-living nematode Caenorhabditis elegans , but the A/B trans isomer 1b was found to be inactive.

Trifunctional ligands, 1-phosphono-1-carbamoyl-n-alkyl ester alkanes [(RO)2P(O)][C(O)NEt2]C(H)[(CH2)nC(O)OR′] (n=1−3) were prepared from metathesis reactions of the metallated anions [(RO)2P(O)][C(O)NEt2]CH− and bromoalkyl esters. The ligands were fully characterized and selected coordination chemistry with La(III), Er(III), UO22+ and Th(IV) was examined. The molecular structures of three coordination complexes were determined by single crystal X-ray diffraction techniques. The 1:1 complex, Er(NO3)3{[(i- PrO)2P(O)][C(O)NEt2]CH[(CH2)2C(O)OMe]}, crystallizes in the monoclinic space group, P21/c with a=9.418(4), b=15.547(7), c=18.259(8) A, β=92.29(4)°, Z=4, V=2671(2) A3 and ϱcalc=1.787 g cm−3. The structure was solved by heavy atom methods and full matrix least-squares refinements converged at RF=3.52% and RwF=4.84% on 4086 reflections with F>6σ(F). The compound forms a polymeric structure in which each Er(III) is nine- coordinate. The Er atom is bonded to three bidentate nitrate ions and the bidentate carbamoylmethyl phosphonate fragment of one trifunctional ligand. It is also bridge bonded to the ester carbonyl group in a second molecular unit. The 2:1 complex, Er(NO3)3{[(i-PrO)2P(O)][C(O)NEt2]CH[(CH2)2C(O)OMe]}2, crystallizes in the monoclinic space group P21/n with a=16.090(8), b=19.114(9), c=17.166(8) A, β=108.01(4)°, Z=4, V=5021(4) A3 and ϱcalc=1.434 g cm−3. The structure was solved by direct methods and refinement converged at RF=4.00% and RwF=4.89% on 5109 independent reflections with F>6σ(F). The compound contains isolated molecules in which the Er(III) is nine-coordinate and bonded to three bidentate nitrate ions, the bidentate carbamoylmethyl phosphonate fragment of one ligand and the phosphonate of a second ligand. The 1:1 complex, UO2(NO3)2{[(i- PrO)2P(O)][C(O)NEt2]CH[(CH2)3C(O)OEt]}, crystallizes in the monoclinic space group P21/c with a=8.855(2), b=16.257(5), c=20.603(6) A, β=92.07(2)°, Z=4, V=2964(1) A3, ϱcalc=1.765 g cm−3. The structure was solved by direct methods and refinement converged at RF=7.82% and RwF=7.77% on 3906 independent reflections with F>3σ(F). The compound contains a linear UO22+ ion bonded to two bidentate nitrate ions and the bidentate carbamoylmethyl phosphonate fragment of the trifunctional ligand. The structures of these complexes are compared with structural data for complexes containing related 1-phosphono-1-carbamoyl-n-carbamoyl alkanes and 1,1-bis- phosphono-n-carbamoyl alkanes.

A series of novel quinoxaline heterocycle containing angiotensin II receptor antagonist analogs were prepared. This heterocycle was coupled to the biphenyl moiety via an oxygen atom linker instead of a carbon atom. Many of these analogs exhibit very potent activity and long duration of effect. Interestingly, the N-oxide quinoxaline analog was more potent than the nonoxidized quinoxaline as in the comparison of compounds 5 vs 30. In order to improve oral activity, the carboxylic acid function of these compounds was converted to the double ester. This change did result in an improvement in oral activity as represented by compound 44.

α-Phenylthio secondary propanamides 1a-e are converted stereospecifically on treatment with NCS to the analogous (Z)-α-phenylthio-β-chloro propenamides 2a-e. Extension to longer chain secondary amide derivatives 1f-g is also possible, albeit less efficiently and without any appreciable stereoselectivity.

C 57 C 29 14 β ,22 R -epithiosteranes 1 were isolated from a Miocene sediment and their structures determined by 1D and 2D NMR. This novel series of sedimentary steroids presumably results from intramolecular incorporation of sulfur on steradiene precursors of algal origin.

Novel aromatic carotenoid derivatives 7 and 8 have been identified by synthesis of reference compounds in a H2/PtO2-hydrogenated fraction from the organic extract of a lake sediment (lake Cadagno, Switzerland). They derive from unreported carotenoids presumably biosynthesized by purple sulfur photosynthetic bacteria (Chromatiaceae) and represent potential biomarkers to establish the occurrence of photic zone anoxia in ancient ecosystems.

The behaviour of the synthetic (−)-16-(aminomethyl)eburnamenine (prepared from apovincamine) with formaldehyde was studied. Carrying out the reaction in acetic acid led to an original dimer, while in trifluoroacetic acid a 12-functionalized eburnamonine was isolated.

With the unambiguous structural characterization of 7,11-cyclobotryococca-5,12,26-triene 1 by NMR, a novel C30 botryococcene-related hydrocarbon skeleton bearing a midchain five-membered ring has been identified in organic-rich sediments from Lake Cadagno (Switzerland). This compound may originate from the green alga Botryococcus braunii (race B) widespread in recent and past environments. Alternatively, it may also be a yet unreported lipid of green sulfur photosynthetic bacteria (Chlorobiaceae) or a microbial transformation product of the farnesol produced by the latter.

Eight analogues of (-)-16-chloro-1-dehydro-6S-bromovincadifformine 1 were synthesized and evaluated for cytotoxicity in L1210 cell culture. None of the new compounds was more active than 1 but the modulation at C6, C16 and on the aromatic ring at C10 informs about structure-activity relationships within this series.

Analogues of the natural antibiotic thiolactomycin, with acetylene-based side chains, have the highest recorded in vitro inhibitory activity against the recombinant Mycobacterium tuberculosis beta-ketoacyl-ACP synthase mtFabH condensing enzyme. In particular, 5-[3-(4-acetyl-phenyl)-prop-2-ynyl]-4-hydroxy-3,5-dimethyl-5H-thiophen-2-one exhibited more than an 18-fold increased potency, compared to thiolactomycin, against this key condensing enzyme, involved in M. tuberculosis mycolic acid biosynthesis. Analogues of the antibiotic thiolactomycin, with acetylene-based side chains, have the highest recorded activity against cloned mtFabH condensing enzyme.