B(C6F5)3/CPA-Catalyzed Aza-Diels-Alder Reaction of 3,3-Difluoro-2-Aryl-3H-indoles and Unactivated Dienes.

Here we report B(C6F5)3/CPA-catalyzed enantioselective aza-Diels-Alder reaction of 3,3-difluoro-2-Aryl-3H-indoles with unactivated dienes to access chiral 10,10-difluoro-tetrahydropyrido[1,2-a]indoles. This protocol allows the formation of pyrazole-based C2-quaternary indolin-3-ones with high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis of the 10,10-difluoro-tetrahydropyrido[1,2-a]indole skeleton was successfully achieved without any reduction in both yield and enantioselectivity.

STK214947, a novel indole alkaloids, inhibits HeLa and SK-HEP-1 cells survival and EMT process by blocking the Notch3 and Akt signals.

Apoptosis and epithelial-to-mesenchymal transition (EMT) are closely associated with tumor survival and metastasis. These are the basic events in tumor occurrence and progression. STK214947 is an indole alkaloid with a skeleton that is similar to that of indirubin. Indole alkaloids have attracted considerable attention because of their antitumor activity. However, the relationship between STK214947 and these basic events remains unknown. In this study, the effects of STK214947 on inducing apoptosis and reversing the EMT process in tumor cells were confirmed. Mild concentrations of STK214947 inhibited tumor cell migration by reversing EMT and significantly regulated the expression of EMT-related proteins, including Notch3, E-cadherin, N-cadherin and vimentin. In addition, STK214947 in high concentration could induce apoptosis by down-regulating Notch3, p-Akt/Akt, and NF-κB, and upregulating Caspase 3. These findings support the further development of STK214947 as a potential antitumor small molecule that targets Notch3 and Akt signal transduction in cancer.

Asymmetric aza-Friedel-Crafts Reaction of Cyclic Ketimines with 5-Aminopyrazole Derivatives: Expedient Access to Pyrazole-Based C2-quaternary Indolin-3-Ones.

A chiral phosphoric acid-catalyzed enantioselective aza-Friedel-Crafts reaction of 5-aminopyrazole derivatives with cyclic ketimines attached to a neutral functional group is reported. This protocol allows the formation of pyrazole-based C2-quaternary indolin-3-ones with high enantioselectivities and regioselectivities. Moreover, gram-scale synthesis of the 5-aminopyrazole-based C2-quaternary indolin-3-ones was performed, with no decrease in the yield and enantioselectivity.

Organocatalyzed Enantioselective Aza-Morita-Baylis-Hillman Reaction of Cyclic Ketimine with α,ß-Unsaturated γ-Butyrolactam.

The enantioselective aza-MBH reaction is an efficient strategy for constructing novel carbon-carbon bonds, providing access to multitudinous chiral densely functionalized MBH products. However, the enantioselective aza-MBH reaction of cyclic-ketimines that would generate a versatile synthon is still missing and challenging. Herein, we developed a challenging direct organocatalytic asymmetric aza-MBH reaction involving cyclic ketimines attached to a neutral functional group. Moreover, the α,ß-unsaturated γ-butyrolactam was utilized as a rare nucleophile alkene in this work. The reactions provide enantiomerically enriched 2-alkenyl-2-phenyl-1,2-dihydro-3H-indol-3-ones, bearing with a tetra-substituted stereogenic center. Moreover, this reaction features high α-selectivities, high enantioselectivities (up to 99% ee), and good yields (up to 80%).

Chiral phosphoric acid-catalyzed enantioselective aza-Friedel-Crafts reaction of naphthols and electron-rich phenols with 2-aryl-3H-indol-3-ones.

The enantioselective aza-Friedel-Crafts reaction is one of the most straightforward and efficient strategies for constructing a new carbon-carbon bond bearing quaternary stereocenter in organic synthesis, but the catalytic asymmetric aza-Friedel-Crafts reaction of naphthols/phenols with cyclic-ketimines attached to a neutral functional group remains still relatively unexplored. Herein, a highly enantioselective aza-Friedel-Crafts reaction of cyclic-ketimines and naphthols/phenols has been realized using a chiral phosphoric acid catalyst. A variety of chiral aminonaphthols (chiral indolin-3-ones) containing a quaternary stereocenter at the C2 position were obtained with excellent outcomes (up to 97% yield, 98% ee). Moreover, the synthetic utility of the enantiomerically enriched chiral aminonaphthols was demonstrated in some efficient transformations. According to the experimental results, a possible transition state model has been proposed to rationalize the origin of asymmetric induction.

B(C6F5)3-catalyzed ß-C(sp3)-H alkylation of tertiary amines with 2-aryl-3H-indol-3-ones.

The ß-C-H functionalization of amines is one of the most powerful tools for the synthesis of saturated nitrogen-containing heterocycles in organic synthesis. However, the ß-C-H functionalization of amines via redox-neutral addition with cyclic-ketimines is still unprecedented. Herein, the ß-C-H functionalization of tertiary amines is described, providing the corresponding 1,3-diamines containing the indolin-3-one moiety in high yields via the B(C6F5)3-catalyzed borrowing hydrogen strategy. According to the experimental results, a possible catalytic cycle has been proposed to rationalize the process of this reaction. Notably, the ß-C-H alkylation of amines is external oxidant- and transition-metal-free, which makes a significant contribution to promoting economical chemical synthesis.

Transcriptome analysis of Armillaria gallica 012 m in response to auxin.

Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant-fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.

Electrochemical Oxidative C-C Bond Cleavage of Ketones for C-N Bond Formation: A Route to Amides.

Herein, we report an efficient electrochemical activation of the C-C bond of aryl ketones for the preparation of amides under catalyst- and external-oxidant-free conditions using aliphatic amines as the N source. Under environmentally benign electrolysis conditions, a series of amides were synthesized in good yield. Our control experiments revealed that electricity plays an important role in this transformation.

Structure Elucidation of Two New Norlignans from Anemone vitifolia and Their Anti-Inflammatory Activities.

Two new norlignans together with two known phenylpropanoids were isolated from the whole herb of Anemone vitifolia. All compounds were reported from this plant for the first time. The structures of these compounds were identified by comprehensive HR-ESI-MS, 1D and 2D NMR spectroscopic data analysis and comparison with literature data. Additionally, bioactivity study results showed that two new compounds have potential anti-inflammatory activity. The plausible biosynthetic pathway for these compounds were also speculated in this article.

CO2/Photoredox-Cocatalyzed Tandem Oxidative Cyclization of α-Bromo Ketones and Amines To Construct Substituted Oxazoles.

CO2/photoredox-cocatalyzed tandem oxidative cyclization of α-bromo ketones and amines for the preparation of substituted oxazoles has been achieved. The avoidance of using both transition-metal catalysts and peroxides makes this method more sustainable and renewable.

[Chemical constituents of Cassia siamea].

A total of ten compounds were isolated from the 90% Et OH extract of Cassia siamea by using various chormatographic techniques,and their structures were established as( 2' S)-2-( propan-2'-ol)-5,7-dihydroxy-benzopyran-4-one( 1),chrobisiamone( 2), 2-( 2'-hydroxypropyl)-5-methyl-7-hydroxychromone( 3), 2,5-dimethyl-7-hydroxychromone( 4), 2-methyl-5-acetonyl-7-hydroxychromone( 5),3-O-methylquercetin( 6),3,5,7,3',4'-pentahydroxyflavonone( 7),luteolin-5,3'-dimethylether( 8),4-( trans)-acetul-3,6,8-trihydroxy-3-methyl-dihydronapht halenone( 9) and 6-hydroxymellein( 10) based on the spectroscopic data.Compound 1 was a new compound,and 3,4,6,8 were isolated from this plant for the first time.

[A new naphthaldehyde derivative from Comastoma pulmonarium and its anti-tobacco mosaic virus (anti-TMV) activity].

A new naphthaldehyde derivative has been isolated from Comastoma pulmonarium by using various chromatographic techniques, including silica gel, Sephadex LH-20, MCI-gel resin and RP-HPLC. This compounds was determined as 5-methoxy-2-methyl-7-(2-oxopropyl)naphthalene-1-carbaldehyde(1) by NMR, MS, IR and UV spectra. This compound was also evaluated for its anti-tobacco mosaic virus (anti-TMV) activity. The result showed that it showed high anti-TMV activity with inhibition rate of 32.8%. The inhibition rate is close to that of positive control (ningnanmycin).

Four New Diterpene Glucosides from Perovskia atriplicifolia.

Four new diterpene glucosides, namely perovskiaditerpenosides A - D (1 - 4), were isolated from the BuOH extract of Perovskia atriplicifolia. Their structures were well elucidated by chemical methods and comprehensive spectroscopic analyses including MS, IR, and NMR (1D and 2D). The newly isolated compounds were screened for their cytotoxic activity against HepG2, NB4, HeLa, K562, MCF7, PC3, and HL60. The obtained results indicated that the new compounds possessed considerable cytotoxic activity.

Three new xanthones from Swertia bimaculata and their anti-5α-reductase activity.

Three new xanthones (1-3), together with five known ones (4-8), were isolated from whole herb of Swertia bimaculata. Their structures were established on the basis of detailed spectroscopic analysis (1D- and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. New isolates were evaluated for their anti-5α-reductase activity. The results revealed that all new compounds showed weak activity with reductase inhibitions of 40.5 ± 2.8, 38.6 ± 2.5, and 48.9 ± 3.0%, respectively.

Three new anthraquinones from the twigs of Cassia fistula and their bioactivities.

Three previously unreported anthraquinones, fistulaquinones A-C (1-3), together with three known ones (4-6) were isolated from the twigs of Cassia fistula. Their structures were determined by means of extensive NMR and MS spectroscopic analyses. All the isolated compounds were tested for their anti-tobacco mosaic virus (anti-TMV) activity, and compound 3 showed significant activity with inhibition rate of 34.5% at 20 µM concentration, even more potent than positive control. Additionally, compounds 1-6 exhibited moderate cytotoxicity with IC50 values ranging from 2.8 to 9.4 µM for some tested human tumor cell lines.

Biomimetic Synthesis of Resveratrol Trimers Catalyzed by Horseradish Peroxidase.

Biotransformation of trans-resveratrol and synthetic (±)-ε-viniferin in aqueous acetone using horseradish peroxidase and hydrogen peroxide as oxidants resulted in the isolation of two new resveratrol trimers (3 and 4), one new resveratrol derivative (5) with a dihydrobenzofuran skeleton, together with two known stilbene trimers (6 and 7), and six known stilbene dimers (8-13). Their structures and relative configurations were identified through spectral analysis and possible formation mechanisms were also discussed. Among these oligomers, trimers 6 and 7 were obtained for the first time through direct transformation from resveratrol. Results indicated that this reaction is suitable for the preparation of resveratrol oligomers with a complex structure.

Antiviral and Cytotoxic Isocoumarin Derivatives from an Endophytic Fungus Aspergillus oryzae.

Oryzaeins A-D (1-4), four new isocoumarin derivatives, along with five known ones (5-9) were isolated from solid cultures of an endophytic fungus Aspergillus oryzae. Their structures were elucidated by detailed spectroscopic analysis and by comparison with reported data of related derivatives. Among them, compounds 1 and 2 represent the first examples of isocoumarins possessing an unusual 2-oxopropyl group and a rare 3-hydroxypropyl group. Compounds 1 and 2 displayed moderate anti-tobacco mosaic virus activities with inhibition rates of 28.4% and 30.6%, respectively, at the concentration of 20 µM. The new compounds showed moderate inhibitory activities against several human tumor cell lines with IC50 values in the range of 2.8-8.8 µM. Supporting information available online at http://www.thieme-connect.de/products.

Icetexane diterpenoids from Perovskia atriplicifolia.

Five new icetexane diterpenoids, namely, perovskatones B-D (1, 3, 4), 1α-hydroxybrussonol (2), and 1α-hydroxypisiferanol (5), were isolated from Perovskia atriplicifolia, together with a new natural product (6) and two known compounds, przewalskin E (7) and brussonol (8). The structures of the new compounds were elucidated by detailed analyses of their MS, IR, 1D, and 2D NMR data. Compounds 1-8 were assayed for their inhibitory hepatitis B virus activities in the HepG 2.2.15 cell line. The results suggested that compounds 1 and 2 possessed noticeable anti-hepatitis B virus activity in vitro, suppressing the replication of hepatitis B virus DNA with selectivity index values of 154.3 and 137.7, respectively.

Ethnobotanical study on ritual plants used by Hani people in Yunnan, China.

BACKGROUND: The Hani people, who reside in Yuanyang County, Honghe Hani and Yi Autonomous Prefecture, Yunnan Province, rely on rice terrace farming as their primary livelihood. They utilize plants in various traditional ritual practices. The Hani people have categorized the value of plants based on their natural attributes and have refined the ways of using different plants in specific rituals through practical observations and experiences derived from their agricultural culture. Although the plants used in these rituals hold significant cultural value, they have yet to be studied from the perspective of ethnobotany. This study aims to approach the ritual plants using ethnobotanical methods. METHODS: Ethnobotanical fieldwork was conducted in 10 villages in Yuanyang County between 2021 and 2023. Data were collected from the local Hani people through semi-structured interviews and participatory observations and 41 informants were interviewed during the field investigations. The frequency of citation (FC) and relative frequency of citation (RFC) were utilized to evaluate the relative importance of ritual plants among the local communities. RESULTS: A total of 36 plant species, belonging to 18 families and 34 genera, were recorded as being used in 11 ritual practices by the Hani people. Rosaceae, Poaceae, and Fabaceae were found to have the highest number of species. Most of the ritual plants used by the Hani people were collected from the wild. FC and RFC analysis showed that the preferred plants for Hani rituals were Rhus chinensis Mill, Oryza sativa L., Phyllostachys sulphurea (Carr.) A. et C. Riv. and Musa basjoo Siebold & Zucc. ex Iinuma. The 11 rituals are all centered around the performance of people, crops and livestock. The Hani people use plants in different rituals mainly based on their biological attributes. CONCLUSIONS: Many rituals of the Hani people are closely related to their production and livelihood, and the plants used in these rituals are deeply rooted in Hani's traditional ecological knowledge and beliefs. The Hani people's reverence for nature, respect for life, gratitude towards ancestors, and seeking blessings and disaster prevention for their families, crops, and livestock are all reflected in these rituals and their utilization of ritual plants. The Hani people showcase their agricultural culture in the Honghe Hani Rice Terraces through plant-based ritual performances. Studying ritual plants in the core area of the Hani Rice Terraces is of great significance for protecting the Hani Terrace farming culture. In the future, it is essential to pay more attention to the role of traditional knowledge in biodiversity conservation.

Asymmetric Organocatalyzed Cyclization Cascade Reactions of 3,3-Difluoro-2-aryl-3H-indoles and Enamides.

The direct functionalization of ß-C(sp2)-H bonds in enamides has garnered increasing attention within the realm of organic synthesis. However, these remarkable advancements are predominantly dependent on transition metals; limited success has been achieved via organocatalytic catalysis. Herein, we report a CPA-catalyzed ß-C(sp2)-H functionalization of enamides cascade intramolecular cyclization to synthesize the chiral dihydropyrimido[1,6-a]indoles bearing gem-difluoromethylene. Moreover, this methodology enables the synthesis of diverse chiral dihydropyrimido[1,6-a]indoles with outstanding enantioselectivities in moderate to high yields.