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An electrochemically regioselective C-H phosphorothiolation of (hetero)arenes with thiocyanate as the S source under ultrasonic irradiation has been developed. The synergistic cooperation of electrooxidation and ultrasonication markedly accelerated the C-H phosphorothiolation reaction. This mechanistically different method is distinguished by its wide substrate scope and transition-metal-free and external-oxidant-free conditions, thus complementing the existing metal-catalyzed or peroxide-mediated protocols for the green synthesis of S-(hetero)aryl phosphorothioates.

A cytochalasan, xylarichalasin A, was obtained from the endophytic fungus Xylaria cf. curta harbored in Solanum tuberosum. Its structure was elucidated by comprehensive spectroscopic methods including HRESIMS, 1D/2D NMR, and residual dipolar coupling analysis as well as quantum chemistry calculations including DFT GIAO 13C NMR and ECD calculation. It has an unprecedented 6/7/5/6/6/6 fused polycyclic structure. In bioassay, xylarichalasin A showed cytotoxicity against human cancer cell lines with IC50 value ranging from 6.3-17.3 μM.

Structurally unique thiopyranodipyridine alkaloids xylaridines C (1) and D (2) were isolated from the fungus Xylaria longipes. Their structures were established by comprehensive spectroscopic analysis combined with single-crystal X-ray diffraction and electron-capture detection (ECD) calculations. Compound 1 possesses two piperidine moieties fused with a centered thiopyran ring, while compound 2 is a dimer of 1. Compound 1 was resoluted into optical pure enatiomers (+)-1 and (-)-1 by chiral HPLC. Moreover, compound 2 was resoluted into an optically pure compound (+)-2 and a mixture of (-)-2 and meso-2. Plausible biosynthetic pathways of compounds 1 and 2 are proposed.

Two highly conjugated alkaloids xylaridines A (1) and B (2) were obtained as racemates from the fungus Xylaria longipes. They were resoluted into optically pure enantiomers, respectively. Their structures were determined by extensive spectroscopic analyses, X-ray diffraction, and equivalent circulating density (ECD) calculations. Compound 1 possesses a 5/6/6/5/5 fused ring system with unique 2-azaspiro[4.4]nonane substructure. The hypothesis of biosynthesis pathways for 1 and 2 was proposed.

A series of inexpensive, easily tunable, and highly reducing organic photocatalysts (PCs) that exhibit strong absorption in the visible region are described. Time-dependent density functional theory calculations were applied to corroborate the experimental observations and explain the relationship between the structure and property. The photocatalytic efficiency of these PCs was demonstrated by catalyzing several challenging reactions and the radical cascade cyclization of 1,6-diyne with superior photocatalytic efficiency to other organic photocatalysts.

Two monoterpenoid indole alkaloids, ophiorrhines A (1) and B (2), were obtained from plant Ophiorrhiza japonica BI. Their structures were elucidated by extensive spectroscopic methods and single crystal X-ray diffraction. Compounds 1 and 2 possess a novel spirocyclic ring system. Its biosynthesis pathway is proposed. Compound 2 exhibits potent inhibitory activity against concanavalin A (Con A) induced T cell proliferation and lipopolysaccharide (LPS) induced B lymphocyte cell proliferation with IC50 values 13.3 and 7.5 μM, respectively. Compound 1 exhibits significant inhibition specifically against the LPS-induced proliferation of B lymphocyte cells with IC50 value 18.6 μM.

Antroalbocin A (1), a sesquiterpenoid possessing a bridged tricyclic system, was isolated from cultures of the higher fungus Antrodiella albocinnamomea (Basidiomycota). The structure with the absolute configuration was determined by extensive spectroscopic methods and single-crystal X-ray diffraction. A plausible biosynthetic pathway for 1 was proposed. Compound 1 was found to inhibit Staphylococcus aureus with an MIC value of 169 μM.

A cytochalasan, xylarichalasin A, was obtained from the endophytic fungus

Curtachalasins C–E (1–3), which have an unprecedent bridged 6/6/6/6 ring system, were identified from the endophytic fungus Xylaria cf. curta. Residual dipolar coupling analyses associating with density functional theory calculations were utilized to determine the relative configuration of noncrystallizable compound 2. The absolute configurations of 1–3 were determined by X-ray diffraction and electronic circular dichroism calculations. Remarkably, curtachalasin C (1) showed significant resistance reversal activity against fluconazole-resistant Candida albicans.

Two trichothecene sesquiterpenoids, trichothecrotocins A (1) and B (2), and a merosesquiterpenoid racemate, (±)-trichothecrotocin C (3), were obtained from potato endophytic fungus Trichothecium crotocinigenum by bioguided isolation. Their structures were elucidated by extensive spectroscopic methods, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Compounds 1 and 2 are trichothecenes possessing new ring systems. Compound 3 possesses a novel 6/6-5/5/5 fused ring system. Compounds 1-3 showed antiphytopathogenic activities with MIC values of 8-128 μg/mL.

Two unique cytochalasans, curtachalasins A (1) and B (2), were purified from the endophytic fungus Xylaria curta E10 harbored in the plant Solanum tuberosum. Their structures were determined by extensive spectroscopic methods, X-ray crystallographic analysis, and electronic circular dichroism calculations. These two compounds feature an unprecedented pyrolidine/perhydroanthracene (5/6/6/6 tetracyclic skeleton) fused ring system.

Four novel heterobimetallic complexes [REL2]{[(THF)3Li]2(μ-Cl)} stabilized by chiral phenoxy-functionalized prolinolate (RE = Yb (1), Y (2), Sm (3), Nd (4), H2L = (S)-2,4-di-tert-butyl-6-[[2-(hydroxydiphenylmethyl)pyrrolidin-1-yl]methyl]phenol have been synthesized and characterized. These readily available complexes are highly active in catalyzing the epoxidation of α,β-unsaturated ketones, while the enantioselectivity varies according to the ionic radii of the rare earth center. A series of chalcone derivatives were converted to chiral epoxides in 80 → 99% ee at 0 °C using TBHP as the oxidant in the presence of 10 mol % of 1.

It was found for the first time that neutral amphiphilc tetraphenylethylene (TPE) derivatives showed an enhanced monomer emission and a decreased aggregate emission when they were included in the cavity of γ-cyclodextrin. This result provided a new insight into the aggregation-induced emission (AIE) effect.

Psychotripine, a trimeric pyrroloindoline derivative with an unprecedented hendecacyclic system bearing a hexahydro-1,3,5-triazine unit, was isolated from the leaves of Psychotria pilifera. The structure was elucidated on the basis of spectroscopic and quantum theory. A possible biogenesis was also postulated.

Melotenine A (1), an unprecedented skeleton with a 6/5/5/6/7 pentacyclic rearranged ring system, was isolated from Melodinus tenuicaudatus. The structure was elucidated by means of spectroscopic methods and further confirmed by the single-crystal X-ray diffraction analysis. A possible biogenesis was also proposed. Melotenine A exhibited potential inhibition against five human cancer cell lines.

A phytochemical study on Melodinus henryi has led to the isolation of two novel alkaloids, melohenines A (1), a monoterpenoid indole alkaloid with additional skeletal carbons arranged compactly in eight rings, and melohenine B (2), an alkaloid with an unprecedented 6/9/6/6 tetracyclic ring system regarded as a key intermediate from indole to quinoline alkaloids. Their structures were elucidated by means of spectroscopic methods and further confirmed by X-ray diffraction analysis.

Conosilane A (1), a novel sesquiterpene with an unprecedented carbon skeleton, was isolated from the cultures of the basidiomycete Conocybe siliginea. Its structure was elucidated by extensive spectroscopic methods, and the absolute configuration was determined by single crystal X-ray diffraction analysis. Conosilane A was found to inhibit 11β-hydroxysteroid dehydrogenase significantly.

Trefolane A (1), an unprecedented skeleton with a 5/6/4 tricyclic ring system, was isolated from cultures of the basidiomycete Tremella foliacea. The structure was elucidated by means of spectroscopic methods and further confirmed by single crystal X-ray diffraction analysis. A possible biogenesis for trefolane A (1) was also proposed.

An unprecedented cage-like alkaloid, scholarisine A was isolated from the leaves of Alstonia scholaris and its structure determined on the basis of 1D and 2D NMR, FTIR, UV, and high-resolution mass spectroscopic data. This alkaloid might be derived from picrinine via oxygenation, rearrangement, and lactonization.