Diastereodivergent and Enantioselective Synthesis of Homoallylic Alcohols via Nickel-Catalyzed Borylative Coupling of 1,3-Dienes with Aldehydes.

We present the first enantioselective nickel-catalyzed borylative coupling of 1,3-dienes with aldehydes, providing an efficient route to highly valuable homoallylic alcohols in a single step. The reaction involves the 1,4-carboboration of dienes, leading to the formation of C-C and C-B bonds accompanied by the construction of two continuous stereogenic centers. Enabled by a chiral spiro phosphine-oxazoline nickel complex, this transformation yields products with exceptional diastereoselectivity, E-selectivity, and enantioselectivity. The diastereoselectivity of the reaction can be controlled by employing either (Z)-1,3-dienes or (E)-1,3-dienes.

Ketone α-alkylation at the more-hindered site.

Control of the regioselectivity of α-alkylation of carbonyl compounds is a longstanding topic of research in organic chemistry. By using stoichiometric bulky strong bases and carefully adjusting the reaction conditions, selective alkylation of unsymmetrical ketones at less-hindered α-sites has been achieved. In contrast, selective alkylation of such ketones at more-hindered α-sites remains a persistent challenge. Here we report a nickel-catalysed alkylation of unsymmetrical ketones at the more-hindered α-sites with allylic alcohols. Our results indicate that the space-constrained nickel catalyst bearing a bulky biphenyl diphosphine ligand enables the preferential alkylation of the more-substituted enolate over the less-substituted enolate and reverses the conventional regioselectivity of ketone α-alkylation. The reactions proceed under neutral conditions in the absence of additives, and water is the only byproduct. The method has a broad substrate scope and permits late-stage modification of ketone-containing natural products and bioactive compounds.

Antibacterial Metabolites from Kiwi Endophytic Fungus Fusarium tricinctum, a Potential Biocontrol Strain for Kiwi Canker Disease.

Pseudomonas syringae pv. actinidiae (Psa) is a Gram-negative bacterium causing the kiwifruit canker disease, resulting in serious economic losses to the kiwifruit industry. This study investigated the use of an endophytic fungus, Fusarium tricinctum, obtained from the kiwi plant (Actinidia chinesis) as a potential biocontrol strain against the Psa. F. tricinctum showed an inhibition rate of 59.5% in vitro against Psa. Bioassay-guided isolation was conducted on the cultural broth of F. tricinctum and seven new imidazole alkaloids, (±)-fusaritricine J ((±)-1) and fusaritricines K-P (2-7), and four enniatins (8-11) were identified. Their absolute configurations were established through extensive spectroscopic methods, quantum chemical calculations, and X-ray single crystal diffraction. Compounds 1, 4, 5, and 8-11 showed comparable anti-bacterial activities against Psa as positive control, with MIC values of 25-50 µg/mL. Further cell membrane permeability assay suggested that the most active compound 4 could destroy the bacterial cell wall structure. Hence, F. tricinctum metabolites could be applied as potential anti-Psa agents, and F. tricinctum could be considered a biocontrol strain for the control of the kiwifruit canker disease.

Chemical constituents from mushroom Geoglossum fallax and their bioactive activities.

Chemical investigation on the fruiting bodies of the mushroom Geoglossum fallax led to the isolation of two carboxamides, geoglamides A and B (1 and 2), one meroterpenoid, geoglol A (3), together with seven known metabolites (4-10). Their structures were identified by spectroscopic analyses as well as ECD calculations. Compounds 1 and 2 are rare long chain fatty amides containing a 4-oxo-1,4-dihydropyridine moiety, while compound 3 is a rare C6-C5 type meroterpenoid. Compound 1 displayed cytotoxic activity against human MCF-7 cells with an IC50 value of 25.9 ± 0.51 µM. compounds 2 and 8 showed weak pancreatic lipase inhibition activity. To our best knowledge, this is the first report of the chemical constituents in the genera Geoglossum and their bioactive activity.

Cadinane sesquiterpenoids from the fungus Antrodiella albocinnamomea and their inhibitory activity against nitric oxide production.

Seven previously undescribed cadinane sesquiterpenoids, albocinnamins A‒G, were isolated from the fungus Antrodiella albocinnamomea. Their structures with absolute configurations were elucidated on the basis of extensive spectroscopic methods, as well as single crystal X-ray diffraction. Cadinane sesquiterpenoids were reported from A. albocinnamomea for the first time. All of these sesquiterpenoids possess an unusual ether ring with minor modifications. Albocinnamins D and G showed certain inhibitory activities against nitric oxide production in LPS-activated RAW264.7 macrophages with IC50 values of 26.1 and 19.2 µM, respectively.

Natural imidazole alkaloids as antibacterial agents against Pseudomonas syringae pv. actinidiae isolated from kiwi endophytic fungus Fusarium tricinctum.

Kiwi (Actinidia chinensis) plants are severely destroyed by canker disease which is caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa). This program tries to find anti-Psa agents among secondary metabolites of endophytic fungi from kiwi plant itself. The chemical investigation on one kiwi endophytic fungi, Fusarium tricinctum, resulted in the isolation of nine new imidazole alkaloids, fusaritricines A-I (1-9) together with seven known analogues (10-16). The structures of new compounds were established by extensive spectroscopic methods. Compounds 2, 3, 9, and 13 showed good antibacterial activity against Psa with MIC values between 25 and 50 µg/mL. It is suggested that imidazole alkaloids should be potential anti-Psa agents.

Advances in Research on Chemical Constituents and Their Biological Activities of the Genus Actinidia.

Kiwi, a fruit from plants of the genus Actinidia, is one of the famous fruits with thousand years of edible history. In the past twenty years, a great deal of research has been done on the chemical constituents of the Actinidia species. A large number of secondary metabolites including triterpenoids, flavonoids, phenols, etc. have been identified from differents parts of Actinidia plants, which exhibited significant in vitro and in vivo pharmacological activities including anticancer, anti-inflammatory, neuroprotective, anti-oxidative, anti-bacterial, and anti-diabetic activities. In order to fully understand the chemical components and biological activities of Actinidia plants, and to improve their further research, development and utilization, this review summarizes the compounds extracted from different parts of Actinidia plants since 1959 to 2020, classifies the types of constituents, reports on the pharmacological activities of relative compounds and medicinal potentials.

Pardinumones A-D: Antibacterial Polyketide-Amino Acid Derivatives from the Mushroom Tricholoma pardinum.

Four polyketide-amino acid derivatives, pardinumones A-D (1-4), were isolated from the wild mushroom Tricholoma pardinum. Their structures together with absolute configurations were characterized by means of spectroscopic data analyses, as well as calculated electronic circular dichroism (ECD) and NMR with sorted training set (STS) protocol analysis. Compounds 1-4 exhibited antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli with MIC values in the range of 6.25-50 µg/mL.

N-Heterocyclic Carbene/Palladium Cascade Catalysis: Construction of 2,2-Disubstitiuted Benzofuranones from the Reaction of 3-(2-Formylphenoxy)propenoates with Allylic Esters.

The cascade catalysis involving N-heterocyclic carbene (NHC) and palladium/ligand was demonstrated. In the presence of a triazolium salt, palladium catalyst, and base, the reaction of 3-(2-formylphenoxy)propenoates and allylic esters proceeded efficiently under mild conditions to afford 2-allylbenzofuran-3-one-2-acetates in moderated to good yields. An asymmetric cascade catalysis was achieved when (R)-BINAP was employed as a chiral ligand, producing enantiomerically enriched 2,2-disubstitiuted benzofuran-3-one derivatives with an ee up to 81%.

[FSH, LH, PRL, E2 and T in 8-17 year old males: investigation and analysis].

OBJECTIVE: To investigate the changes of follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), estradiol (E2) and testosterone (T) in male adolescents of different ages by determining their levels in 8-17 years old boys. METHODS: We included in this study 627 male adolescents aged 8-17 years and qualified through physical examinations. All the subjects underwent determination of FSH, LH, PRL, E2 and T with an automatic ACCESS microparticle chemiluminescence immunoassay analyzer and detection of liquid quality control by immunoassay. RESULTS: FSH remained at a low level in the 8-10 years old male adolescents and increased at 11 years; the levels of LH and T were low before the age of 12 years and began to increase at 13 years; and that of E2 was low before the age of 13 years and began to rise after that, all with statistically significant differences (P < 0.01). CONCLUSION: In the male adolescents, FSH, LH and T significantly increased at 11, 12 and 13 years old, respectively, which marked the beginning of sexual development.

[Effect of Zhenyangjian on the penile hemodynamics of the patients with arterial erectile dysfunction].

OBJECTIVE: To explore an efficacious therapy for arterial erectile dysfunction (ED) by observing the effect of the Chinese traditional medicine Zhenyangjian on the penile hemodynamics of the patient. METHODS: Forty-seven patients with arterial ED, aged from 40 to 49 years, were treated with Zhenyangjian for 1 month. Intracavernous injection of papaverine and phentolamine (30 mg/l mg) was given and multifunctional color Doppler ultrasound was used to measure the peak systolic velocity(PSV) of the corpus cavernous arteries before and after Zhenyangjian administration. RESULTS: The PSV of the penis corpus cavernous arteries was obviously ameliorated in all the patients (P < 0.05). CONCLUSION: The Chinese traditional medicine Zhenyangjian can promote penile erection effectively.