Rimp lethality1. Introduction Marine fungi are identified to become a prolific supply of biologically active all-natural goods which might be beneficial for drug discovery [1,2]. As a unique ecosystem, marine sediment offers an abundant of fungal sources, which yielded several secondary metabolites with novel structures and fascinating biologicalMar. Drugs 2013,activities [3?]. In the course of our look for bioactive metabolites from marine-derived fungi [6?1], a strain of Penicillium pinophilum SD-272, which was isolated from sediment samples collected from the estuary of your Pearl River in South China Sea, attracted our attention. The EtOAc extract from the culture extract yielded a new diketopiperazine derivative, pinodiketopiperazine A (1), a new phthalide derivative, six,7-dihydroxy-3-methoxy-3-methylphthalide (2), too as alternariol 2,4-dimethyl ether (3) [12,13] and L-5-oxoproline methyl ester (4) [14], which were isolated from a all-natural source for the initial time but have been previously synthesized (Figure 1). In addition, six identified compounds (5?0) had been also isolated and identified. We present herein the isolation, structural elucidation, absolute configuration determination, and biological activity of these compounds. Figure 1. Structures of your isolated compounds 1?0 as well as the reference compound 11.O3′ 1′ 10 six 1 ROH NH H3 7OMe O14 1 S 16 5 7 1 13O HN OMe O15 1 six 5 3′ 1’O10 9 1HO OH7aN HN5’O OMe3aN5’O H O1HOO 3 OO O O3’OMe OHO3’1’N HHO1OH MeO7a 1 5HN5’OHN HHO7a 1 three 3aOSHNO1′ 5’OMeO33aOOOHOMe HOR 9 R = -OH ten R = -OH2. Outcomes and Discussion 2.1. Structure Elucidation from the New Compounds Compound 1 was obtained as yellowish oil and HRESIMS information established its molecular formula as C15H18N2O3, indicating eight degrees of unsaturation. In the 1H NMR spectrum (Table 1), signals for a mono-substituted phenyl group (H-2 -6) in addition to a tri-substituted double bond (H-10) had been presented, as well as a nitrogenated or oxygenated methine (H-3), three methylenes (H-7 -9), in addition to a tertiary methyl (H-11) group. The 13C and DEPT NMR spectroscopic information (Table 1) exhibited the presence of 15 carbon signals which were further classified into one particular methyl, 3 methylenes (with one particular oxygenated), seven methines, and four quaternary (with two amide ester carbonyl and two olefinic quaternary) carbon atoms. The 1H?H COSY spectrum (Figure 2) revealed two spin systems corresponding to two substructures, together with the very first one particular being a phenyl group which connected for the double bond as evidenced by the HMBC correlation from H-10 to C-2/C-6 (Figure two).1-Cyclopentyl-1h-1,2,4-triazole structure The second substructure getting began from an exchangeable NH proton (NH-2), followed by a methine proton H-3, which connected to a straight chain consisting of three methylene groups (CH2-7 H2-9) and terminated with an OH group (Figure two).BuyP(t-Bu)3 Pd G4 The connection of the above substructures in 1 as talked about above was established by detailed inspection from the essential HMBC correlations from H-10 to C-1, from H3-11 to C-4 and C-6, and from NH-Mar.PMID:23789847 Drugs 2013,to C-4 and C-6. The structure of compound 1 was as a result elucidated as shown in Figure 1. A trivial name pinodiketopiperazine A was assigned to this compound. Figure 2. Crucial COSY (bold lines) and HMBC (arrows) correlations for compounds 1and 2.10 3′ 1’OOH NH3 9HO OHO1 3 3a7aN5′ 11O OMeOTable 1. 1H- and 13C-NMR information of compound 1 in DMSO-d6 a.No. 1 2-NH 3 4 six 7 8 C 162.5, C 55.0, CH 167.9, C 132.four, C 30.six, CH2 28.0, CHaH (J in Hz) 8.62, d (two.eight) three.94, ma 1.79, m b 1.71, m 1.51, mNo. 9 10 11.