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Four new polyketides, namely furantides A-B ( 1 - 2 ), talamin E ( 3 ) and arugosinacid A ( 4 ), and two known polyketides were obtained from the mangrove-derived fungus Penicillium sp. HDN15-312 using the One Strain Many Compounds (OSMAC) strategy. Their chemical structures, including configurations, were elucidated by detailed analysis of extensive NMR spectra, HRESIMS and ECD. The DPPH radicals scavenging activity of 3 , with an IC 50 value of 6.79 µM, was better than vitamin C.

Six new α-pyrone polyketides, penipyrols C-G (1-5) and methyl-penipyrol A (6), together with one biogenetically related known compound, penipyrol A (7), were isolated from the extract of fungus Penicillium sp. HDN-11-131. Their structures including the absolute configurations were established by extensive spectroscopic analysis, Mosher's method, and ECD calculations as well as biogenic considerations. Compounds 1-4 possess a rare skeleton featuring γ-butyrolactone linked to α-pyrone ring through double bond. Compound 1 can induce pancreatic β-cell regeneration in zebrafish at 10 μM, which demonstrated promising anti-diabetes potential., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Three new polyketides, ketidocillinones A-C ( 1 - 3 ), were discovered from the extract of an Antarctica sponge-derived fungus Penicillium sp. HDN151272. All the structures were deduced by spectroscopic data, including NMR and HRESIMS. The absolute configuration of compound 3 was established by using ECD calculation. Compounds 1 - 3 can be slowly oxidized to quinone form when exposed to air. Ketidocillinones B and C ( 2 and 3 ) exhibited potent antibacterial activity against Pseudomonas aeurigenosa , Mycobacterium phlei, and MRCNS (methicillin-resistant coagulase-negative staphylococci ) with MIC values ranging from 1.56 to 25.00 µg/mL., Competing Interests: The authors declare no conflict of interest.

Two new polyketides modified with a rare methylsulfonyl group, 3-methoxy-6-methyl-5-(methylsulfonyl)benzene-1,2,4-triol (1) and neosartoryone A (2), along with a biogenetically related compound (3), were isolated from Neosartorya udagawae HDN13-313 cultivated with the DNA methyltransferase inhibitor 5-azacytidine. The methylsulfonyl group of 1 and 2 was proven to be derived from DMSO, which was used as the solvent to dissolve 5-azacytidine. This is the first report of a fungus that can achieve a sulfonylation-like modification of natural products utilizing DMSO as a sulfur source. Compound 2 showed lipid-lowering activity in vitro comparable to simvastatin.

Four new tetramic acids, cladosins H-K (1-4), and a related known compound, cladodionen (5), were isolated from the culture of the Mariana Trench (depth 6562 m) sediment-derived fungus Cladosporium sphaerospermum L3P3 treated with the histone deacetylase inhibitor SAHA (suberanilohydroxamic acid). Interestingly, compounds 1-5 existed as equilibrium E/ Z mixtures and 1-4 were the first cases of tetramic acids containing aniline moieties. Their structures including absolute configurations were elucidated through a combination of NMR, MS, and Mosher's method, together with the consideration of biogenetic origins. Incubation experiments of exogenous aniline and N-phenyloctanamide revealed that the aniline moiety in cladosins H-K (1-4) is probably derived from the degradation of SAHA, indicating that the well-known histone deacetylase inhibitor SAHA could be metabolized by L3P3 and provide aniline as a precursor for biotransformation of chemically reactive polyketides. The cytotoxicity of 1-5 was evaluated against the PC-3, MGC-803, SH-SY5Y, HCT-116, K562, and HL-60 cell lines, and compound 2 showed promising cytotoxicity against the HL-60 cell line with an IC 50 value of 2.8 μM.

Two new nitrogen-containing sorbicillinoids named sorbicillasins A and B ( 1 and 2 ) and a new 3,4,6-trisubstituted α -pyrone derivative, scirpyrone K ( 3 ), together with two known biosynthetically related polyketides ( 4 ⁻ 5 ), were isolated from the deep-sea-derived fungus Phialocephala sp. FL30r by using the OSMAC (one strain-many compounds) method. The structures of 1 ⁻ 3 , including absolute configurations, were deduced based on MS, NMR, and time-dependent density functional theory (TD-DFT) calculations of specific ECD (electronic circular dichroism) spectra. Compounds 1 and 2 possessed a novel hexahydropyrimido[2,1- a ] isoindole moiety, and compound 3 exhibited weak radical scavenging activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) with an IC 50 value of 27.9 μM.

Seven new polyketides, named tanzawaic acids R-X ( 1 - 6 , 11 ), along with seven known analogues ( 7 - 10 and 12 - 14 ), were isolated from Penicillium steckii HDN13-279. Their structures, including the absolute configurations, were elucidated by NMR, MS, X-ray diffraction, circular dichroism (CD) analyses and chemical derivatization. Five compounds ( 2 , 3 , 6 , 10 and 12 ) significantly decreased the oleic acid (OA)-elicited lipid accumulation in HepG2 liver cells at the concentration of 10 μM, among which, four compounds ( 3 , 6 , 10 and 12 ) significantly decreased intracellular total cholesterol (TC) levels and three Compounds ( 3 , 6 , and 10 ) significantly decreased intracellular triglyceride (TG) levels. Moreover, the TG-lowering capacities of compounds 6 and 10 were comparable with those of simvastatin, with the TG levels being nearly equal to blank control. This is the first report on the lipid-lowering activity of tanzawaic acid derivatives., Competing Interests: The authors declare no conflict of interest.

Abstract: Three novel carbon-bridged citrinin dimers, dicitrinones A–C (1–3), were isolated from a volcano ash-derived fungus Penicillium citrinum. Their structures were elucidated by spectroscopic methods. Dicitrinone A (1) and B (2) are two atropisomeric mixtures, which were verified by both NMR and quantum chemical calculations. Their cytotoxicity against four tumor cell lines (HL-60, MOLT-4, A-549, and BEL-7402) was evaluated by SRB and MTT methods. Dicitrinone B (2) arrested the HL-60 cell cycle at the G2/M phase, which was analyzed using flow cytometry. [ABSTRACT FROM AUTHOR]