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The structure of the title compound, C17H20O4 [systematic name: (1aS,3aR,4aS,5aR)-15-(acetoxy)linden-7(11),8-trieno-12,8-lactone or (4aR,5S,5aR,6aS,6bR)-5-(acetoxymethyl)-4a,5,5a,6,6a,6b-hexahydro-3,6b-dimethylcyclopropa[2,3]indeno[5,6-b]furan-2(4H)-one, ent-chloranthalactone C], a natural product isolated from the whole plant Chloranthus japonicus Sieb., is a typical lindenane-type sesquiterpenoid. The molecule comprises a bicyclo[3.1.0]hexane ring (A/B system) bearing an acetoxymethyl (C-4) group, a bicyclo[4.3.0]nonane ring (B/C system) containing a double bond (C-8/9) and a chiral quaternary carbon (C-10), and a 7(11)-en-12,8-olide structural moiety on the cyclohexan-8-ene (C ring). In the tetracyclic skeleton, the 1,3-cyclopropane ring has a β-configuration, and atoms H-5 and H3-14 have α- and β-orientations, respectively. In the crystal, the molecules are assembled into a two-dimensional network by weak O...H/H...O interactions. Hirshfeld surface analysis illustrates that the greatest contributions are from H...H (55.2%), O...H/H...O (34.6%) and C...H/H...C (8.9%) contacts.

The primary hydrogen (H) source for all organic compounds in the biosphere is from water, and then participates in biogeochemical cycles through photosynthesis and plant physiological metabolism. As a new proxy of paleoclimate and paleoenvironment, stable hydrogen isotope ratios in wood lignin methoxyl groups (δ在森林树木合成的有机化合物中,氢元素(H)主要源于大汽水,经植物光合与生理代谢参与生物地球化学循环。近年来,树轮木质素甲氧基稳定氢同位素比率(δ

A novel sesquiterpenoid dimer, named multistalide C (1), together with two known congeners, shizukaols C (2) and D (3), was isolated from the whole plant of Chloranthus japonicus Sieb. The structures of compounds 1-3 were elucidated by extensive HR-ESI-MS, 1D, and 2D NMR spectroscopic analysis. Compounds 1-3 exhibited significant toxic effects on brine shrimp larvae (Artemia salina). The absolute configuration of 1 was established by CD/TDDFT calculations. The related compound chlorahololide A was also reinvestigated. The previous assignment of the absolute configuration of chlorahololide A and several related sesquiterpenoid dimers, based on an incorrect application of the exciton chirality method, is criticized.

Previous studies have demonstrated that patients with obstructive sleep apnea (OSA) may develop left ventricular (LV) diastolic dysfunction. We aimed to study whether OSA patients have LV regional systolic dysfunction with myocardial deformation changes, despite a normal LV ejection fraction, using real-time 3D speckle-tracking echocardiography (Rt3D-STE). Seventy-eight patients with OSA and no comorbidities were studied. They were divided into the following three groups according to the apnea–hypopnea index (AHI): 5~15/h as group I (mild OSA, 26 cases), 15~30/h as group II (moderate OSA, 29 cases), and ≥30/h as group III (severe OSA, 23 cases). Thirty gender–age-matched normal subjects were included as controls. The parameters of LV diastolic function were acquired with traditional echocardiography. The LV myocardial deformation parameters were obtained, including the longitudinal (LS), circumferential (CS), radial (RS), and area (AS) strains, with Rt3D-STE. LV global systolic function was normal in all patients, but diastolic function was impaired in groups II and III (E/E′ was 9.6 ± 2.8 and 10.4 ± 2.5, respectively, p

Two new sesquiterpenes, namely, 1β,10β-dihydroxy-eremophil-7(11), 8-dien-12,8-olide (1) and 8,12-epoxy-1β-hydroxyeudesm-3,7,11-trien-9-one (2), together with three known sesquiterpenoids, shizukolidol (3), 4α-hydroxy-5α(H)-8β-methoxy-eudesm-7(11)-en-12,8-olide (4), and neolitacumone B (5), and two known monoterpenes, (3R,4S,6R)-p-menth-1-en-3,6-diol (6) and (R)-p-menth-1-en-4,7-diol (7), were isolated from the whole plant of Chloranthus japonicus Sieb. Their structures were elucidated on the basis of spectroscopic data analysis and comparison with those of related known compounds. Compounds 4–7 were isolated from this plant for the first time.

This paper gives a detailed discuss in the construction of teaching system, discusses the characteristics of professional teaching practice reform, and lays stress on the approaches and methods of the college students' engineering practical ability training. The reform consist of three fields, the first is designing of the professional teaching program based on the characteristics of engineering practice, which is composed of theory teaching and practice teaching system and Increase the proportion of professional teaching practice, give prominence to project practice. The second is strengthening the construction of inside workplace environment, cultivate of the students' engineering consciousness”. The last is strengthening the humanism quality, innovative quality and engineering quality. In short, College students' comprehensive quality training is a systems engineering, No matter from teaching planned arrangements and implementation, or the actual environment construction, tremendous efforts are needed.

A highly oxygenated new lanostane triterpene, designated as ganodermacetal ( 1 ), together with 15 related known compounds, has been isolated from the fruiting bodies of the basidiomycetous fungus Ganoderma amboinense. The structure of the new metabolite was elucidated on the basis of extensive spectroscopic analyses and chemical transformations. Ganodermacetal ( 1 ) possesses an uncommon 7,15-acetonide unit. Some of the isolated compounds showed significant toxic activity against brine shrimp larvae.

The title compound, C23H35NO2, is an amide derivative of the lactone (+)-sclareolide, and was synthesized from natural sclareol. In the molecular structure, the two six-membered rings (AandB) of the labdane skeleton aretrans-fused, and adopt chair conformations. There is an intramolecular N—H...O hydrogen bond present forming anS(7) ring motif. In the crystal, O—H...O hydrogen bonds link the molecules into helical chains propagating along theb-axis direction. The chains are linkedviaC—H...π interactions, forming a three-dimensional structure.

The title compound, C30H42N2O7[systematic name: (1S,4S,5S,7S,8S,9S,10S,11S,13R,14S,16S,17R)-20-ethyl-4,8,9-trihydroxy-1,14,16-trimethoxyaconitan-4-yl 2-aminobenzoate], isolated from roots ofAconitum sinomontanumNakai, is a typical aconitane-type C19-diterpenoid alkaloid, which crystallizes with two independent molecules in the asymmetric unit. The conformations of the two independent molecules are closely similar. Each molecule comprises four six-membered rings (A,B,DandE) including one six-membered N-containing heterocyclic ring (E), and two five-membered rings (CandF). RingsA,BandEadopt chair conformations, while ringDdisplays a boat conformation. Five-membered ringsCandFexhibit envelope conformations. IntramolecularN—H...O hydrogen bonds between the amino group and carbonyl O atom help to stabilize molecular structure. In the crystal, O—H...O hydrogen bonds link the molecules into zigzag chains propagating in [010].

The title compound, C15H22O3·H2O, is a natural producr isolated fromChloranthus japonicus, which is a eudesmane sesquiterpenoid. The twotrans-fused six-membered rings have chair confomations. In the crystal, O—H...O hydrogen bonds link the components into corrugated layers parallel to thebcplane. There are C—H...O interactions present within and between the layers.

Seven known compounds, three diketopiperazine alkaloids, 12β-hydroxyverruculogen TR-2 (1), fumitremorgin C (2) and methylthiogliotoxin (5), two hetero-spirocyclic γ-lactam alkaloids, pseurotin A (3) and FD-838 (4), and cerevisterol (6) and herierin IV (7), were isolated from the mycelia of the basidiomycete Hericium erinaceum and identified by spectroscopic analyses. The antioxidant and antifungal activities of compounds 1-6 were evaluated. The results indicated that compounds 1, 3 and 6 exhibited potential antioxidant activity against DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical with their IC50 data of ca. 12 μM, compared with positive control tertiary butylhydroquinone. In addition, compound 4 significantly inhibited the growth of two plant fungal pathogens Botrytis cinerea and Glomerella cingulata with an minimum inhibitory concentration of 6.25 μM for each, similar to that of the positive fungicide, carbendazim. Compounds 1-5 were isolated from the genus Hericium for the first time.

Seven known compounds, three diketopiperazine alkaloids, 12β-hydroxyverruculogen TR-2 (1), fumitremorgin C (2) and methylthiogliotoxin (5), two hetero-spirocyclic γ-lactam alkaloids, pseurotin A (3) and FD-838 (4), and cerevisterol (6) and herierin IV (7), were isolated from the mycelia of the basidiomycete Hericium erinaceum and identified by spectroscopic analyses. The antioxidant and antifungal activities of compounds 1–6 were evaluated. The results indicated that compounds 1, 3 and 6 exhibited potential antioxidant activity against DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical with their IC50 data of ca. 12 μM, compared with positive control tertiary butylhydroquinone. In addition, compound 4 significantly inhibited the growth of two plant fungal pathogens Botrytis cinerea and Glomerella cingulata with an minimum inhibitory concentration of 6.25 μM for each, similar to that of the positive fungicide, carbendazim. Compounds 1–5 were isolated from the genus Hericium for the first time.

The title compound (common name: sclaral), C16H28O2, is a sclareolide derivative, which was synthesized from sclareolide itself. In the molecule, the two six-membered rings,AandB, of the labdane skeleton adopt chair conformations and the five-membered O-containing heterocyclic ringCdisplays an envelope conformation, with the methine C atom of the fused C—C bond as the flap. In the crystal, molecules are linked by O—H...O hydrogen bonds, forming chains propagating along [100].

The title compound [systematic name: [(1α,14α,16β)-20-ethyl-8,9,10-trihydroxy-1,14,16-trimethoxyaconitan-4-yl 2-aminobenzoate], C30H42N2O8, a natural C19-diterpenoid alkaloid, possesses an aconitane carbon skeleton with four six-membered rings and two five-membered rings. The fused ring system contains two chair, one boat, one twist-boat and two envelope conformations. Intramolecular N—H...O hydrogen bonds are observed between the amino and carbonyl groups. The molecules are linked togetherviaO—H...O hydrogen bonds, forming a three-dimensional framework.