Three New Chromone Derivatives Produced by Phomopsis sp. HNY29‐2B from Acanthus ilicifolius Linn.

Abstract

Three new chromone derivatives, phomochromenones A‐C (1–3), and one known chaetocyclinone B (4) were obtained from the cultures of Phomopsis sp. HNY29‐2B isolated from the mangrove Acanthus ilicifolius Linn., which was collected from the South China Sea. Their structures were determined by the analysis of 1D NMR and 2D NMR as well as mass spectroscopic data. The absolute configurations of 1 and 2 were assigned by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compound 3 is the third example of alkaloids possessing the unique chromeno [3,2‐c] pyridine nucleus. In the bioactivity assay, compound 4 showed cytotoxicity against human prostate cancer cell lines (PC‐3 and DU145 cells) with the IC50 values of 8.13 and 3.59 µmol/L, respectively.

Bioactive Secondary Metabolites of the Genus Diaporthe and Anamorph Phomopsis from Terrestrial and Marine Habitats and Endophytes: 2010–2019

“…ilicifolius Linn. Compound 39 had cytotoxic activity against PC-3 (IC 50 = 8.13 μmol/L) and DU145 (IC 50 = 3.59 μmol/L) [ 36 ]. The fungus Phomopsis sp.…”

Diaporphasines E and F: New Polyketides from the Saprotrophic Fungus Lachnum sp. IW157 Growing on the Reed Grass Phragmites communis

“…The 1 H NMR spectral data of 1 (Table , Figure S3) disclosed the presence of four aromatic protons distinguished into two deshielded aromatic protons at δ H 9.13 and δ H 7.40 that were correlated by the HSQC spectrum to two olefinic carbons at δ C 148.7 and δ C 110.3, respectively, suggesting the presence of an ortho - para- trisubstitued pyridine moiety in its structure. − In addition, the 1 H NMR spectrum of 1 revealed two more aromatic protons at δ H 7.39 and δ H 6.84 that were directly correlated in the HSQC spectrum to two carbon atoms at δ C 108.0 and δ C 102.7, respectively. The 1 H– 1 H COSY spectrum of 1 (Figure , Figure S5) unveiled the existence of a key correlation extending from a methylene group at δ H 2.82 (t, J = 7.5 Hz, H 2 -11) over seven methylene groups at δ H 1.70 (q, J = 7.5 Hz, H 2 -12) and δ H 1.28 (m, H 2 -13), three methylene groups at δ H 1.20–1.25 (m, H 2 -14 to H 2 -16), δ H 1.22 (m, H 2 -17), and δ H 1.26 (m, H 2 -18), and a methyl triplet at δ H 0.83 (t, J = 6.8 Hz, H 3 -19), suggesting the presence of a n -nonyl aliphatic side chain.…”

Four New Chromones from the Endophytic Fungus Phomopsis asparagi DHS-48 Isolated from the Chinese Mangrove Plant Rhizophora mangle

“…The 13 C NMR and DEPT spectra showed 20 carbon signals, including a keto group, an ester carbonyl group, eight olefinic carbon signals (including four oxygenated carbons), three oxy-methines, one methylene, two methoxy group, and three methyl group. Comparison of the NMR data of 4 with those of phomochromenone B [ 21 ], previously isolated from endophytic fungus Phomopsis sp. HNY29-2B derived from mangrove plant Acanthus ilicifolius Linn, revealed that both compounds differed with regard to the nature of the side chain at C-1, where the hydroxyl group of the latter was replaced by the 3-hydroxybutan-2-yloxyl group of 3 .…”

“…As part of our ongoing investigation on bioactive metabolites from mangrove endophytic fungi [ 15 , 16 , 17 , 18 , 19 ], Phomopsis asparagi DHS-48 was isolated from a fresh root of the mangrove plant Rhizophora mangle . Four new chromones ( 1 – 4 ), and five known compounds, including diaporchromone A ( 5 ) [ 20 ], diaporchromanone C ( 6 ) [ 20 ], diaporchromanone D ( 7 ) [ 20 ], and phomochromenone C ( 8 ) [ 21 ] ( Figure 1 ) were isolated from the EtOAc extract of P. asparagi after fermentation on a solid rice medium containing sea salt. Herein, we report the isolation, structural elucidation, and exploration on the biological activities of compounds 1 – 8 .…”