Five unusual macrolides, gliomasolides A-E (1-5), were isolated from a sponge-derived fungus Gliomastix sp. ZSDS1-F7-2. Their structures were established by extensive spectroscopic analyses and singlecrystal X-ray diffraction studies. Structurally in common, these compounds feature a very rare 14-membered macrocyclic backbone lacking of methyl group. Cytotoxic effect of these metabolites against the growth of HeLa cell lines was evaluated, revealing that 1 exhibited moderate inhibitory effect with an IC 50 value of 10.1 mM.Natural products have been a rich source of drugs and drug leads for many years. 1 Macrolides, frequently discovered from various marine microorganisms, are of particular importance to this end because of their signicant biological effects and unique structures, 2 which therefore make them prominent targets for both synthetic chemists and pharmacologists. 3 As versatile members of the large macrolides family, 14-membered macrolides attract tremendous attention since they oen demonstrate excellent pharmacokinetics and efficacy: interesting examples involving clarithromycin and erythromycin, 4 both of which have been approved by US FDA for the treatment of bacterial infections.As a result of our continuous investigation of bioactive metabolites from marine organisms, 5 we have discovered ve unusual 14-membered macrolides, gliomasolides A-E (1-5) ( Fig. 1), produced by the fungus Gliomastix sp. ZSDS1-F7-2 (see ESI †) from the marine sponge Phakellia fusca Thiele, which was collected from the South China Sea in March 2012. Herein, we report the isolation, structural elucidation, and biological activity of these unusual metabolites.First, the strain Gliomastix sp. ZSDS1-F7-2 was incubated in 100 mL Erlenmeyer ask containing 25 mL of malt medium (20 g L À1 of malt extract, 1 g L À1 of peptone, and 30 g L À1 of sea salt, 20 Â 100 mL asks) on a rotary shaker (180 rpm) at 25 C to give the seed culture, which was transferred to the 1000 mL Erlenmeyer ask containing solid rice medium (200 g of rice, 200 g water, 6 g sea salt, 20 Â 1 L asks). Aer static incubation at 25 C under daylight for 2 months, the culture was broken up with a spatula and extracted three times with 95% ethanol (EtOH). Then, the combined 95% EtOH crude extract was suspended in water and subsequently extracted with petroleum ether, ethyl acetate (EtOAc), and n-butanol. From the EtOAc extract, ve novel macrolides, gliomasolides A-E (1-5), were isolated by serial column chromatography on silica gel, octadecyl silane (ODS), and preparative reversed-phase highperformance liquid chromatography (HPLC).Compound 1 possessed a molecular formula C 18 H 32 O 4 as determined by HRCIMS ion peaks at m/z 313.2383 [M + H] + and 295.2268 [M À H 2 O + H] + (calcd for C 18 H 33 O 4 and C 18 H 31 O 3 , m/z 313.2379 and 295.2273, respectively), indicative of three doublebond equivalents (DBEs). 13 C NMR spectrum conrmed the presence of 18 carbon atoms, which by HSQC experiment were classied into one methyl, eleven methylenes, three oxygenated me...

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Eleven new sesquiterpenoids, wenyujinins A-K (1-11), and a new monoterpenoid, wenyujinin L (12), were isolated from the rhizomes of Curcuma wenyujin. Their structures and relative configurations were elucidated using 1D and 2D NMR, X-ray crystallographic analysis, and HRESIMS data. The absolute configurations of 1, 2, 3, 4, 6, 8, 9, and 10 were determined by comparison of the experimental and calculated ECD spectra. The absolute configuration of 5 was determined from the ECD data of the [Rh2(OCOCF3)4] complex, whereas those of 7 and 12 were determined from the ECD spectra of the compounds alone. Compounds 7 and 7a strongly inhibited the induction of NO production by LPS, with IC50 values of 7.6 and 8.5 μM, respectively. Compounds 6 and 10 moderately inhibited NO production with IC50 values of 47.7 and 48.6 μM, respectively.

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