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The isolation and structure determination of a new chlorinated benzophenone antibiotic, pestalone (1), is described. The new compound was produced by a cultured marine fungus only when a unicellular marine bacterium, strain CNJ-328, was co-cultured in the fungal fermentation. The fungus, isolated from the surface of the brown alga Rosenvingea sp. collected(More)
The endophytic fungus Periconia sp. produces piperine (5-(3, 4-methylenedioxyphenyl)-1-piperidinopent-2, 4-dien-1-one) under liquid culture. This is the first report of the alternative source for this chemical other than its host, Piper longum. The highly functionalized fungus-derived piperine exhibits strong antimycobacterial activity against Mycobacterium(More)
Trichodermamides A (1) and B (2), two modified dipeptides, have been isolated from cultures of the marine-derived fungus Trichoderma virens. The trichodermamides possess a rare cyclic O-alkyl-oxime functionality incorporated into a six-membered ring. The structure of trichodermamide B was established by X-ray diffraction analysis, while the structure(More)
Two novel cyclic depsipeptides, guangomides A (1) and B (2), together with a new destruxin derivative (3) were isolated from the cytotoxic extract obtained from the saltwater culture of an unidentifiable sponge-derived fungus. The new structures were elucidated on the basis of analysis of extensive 1D and 2D NMR data sets, and the absolute configurations of(More)
The structure of the class C ampC beta-lactamase (cephalosporinase) from Enterobacter cloacae strain P99 has been established by x-ray crystallography to 2-A resolution and compared to a class A beta-lactamase (penicillinase) structure. The binding site for beta-lactam (penicillinase) structure. The binding site for beta-lactam antibiotics is generally more(More)
A series of zinc(II) and magnesium(II) alkoxides based upon a beta-diiminate ligand framework has been prepared. [(BDI-1)ZnO(i)Pr](2) [(BDI-1) = 2-((2,6-diisopropylphenyl)amido)-4-((2,6-diisopropylphenyl)imino)-2-pentene] exhibited the highest activity and stereoselectivity of the zinc complexes studied for the polymerization of rac- and meso-lactide to(More)
The crystal structure of a complex formed on reaction of the Enterobacter cloacae P99 cephalosporinase (beta-lactamase) with a phosphonate monoester inhibitor, m-carboxyphenyl [[N-[(p-iodophenyl)acetyl]amino]methyl]phosphonate, has been obtained at 2.3-A resolution. The structure shows that the inhibitor has phosphonylated the active site serine (Ser64)(More)
The impact of redox non-innocence (RNI) on chemical reactivity is a forefront theme in coordination chemistry. A diamide diimine ligand, [{-CH=N(1,2-C6H4)NH(2,6-iPr2C6H3)}2](n) (n = 0 to -4), (dadi)(n), chelates Cr and Fe to give [(dadi)M] ([1Cr(thf)] and [1Fe]). Calculations show [1Cr(thf)] (and [1Cr]) to have a d(4) Cr configuration antiferromagnetically(More)
Polymerization of beta-butyrolactone (BBL) and beta-valerolactone (BVL) using the zinc alkoxide initiator (BDI-1)ZnO(i)()Pr [(BDI-1) = 2-((2,6-diisopropylphenyl)amido)-4-((2,6-diisopropylphenyl)imino)-2-pentene] proceeds very rapidly under mild conditions to produce poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxyvalerate) (PHV), respectively. For the(More)