COAP-Pd Catalyzed Asymmetric Formal [3+2] Cycloaddition for Optically Active Multistereogenic Spiro Cyclopentane-Indandiones Bearing Cyclic N-Sulfonyl Ketimine Skeletons.

We reported a chiral oxamide-phosphine ligand (COAP-Ph)-Pd-catalyzed asymmetric [3+2] cycloaddition reaction between vinyl cyclopropane derived from 1,3-indanedione and 2-vinylcyclopropane-1,1-dicarboxylates with cyclic sulfonyl 1-azadienes. The corresponding reactions provided a series of enantiomerically active spiro cyclopentane-indandione and cyclopentane structures bearing three consecutive stereogenic centers in good yields with good diastereo- and enantioselectivity. The COAP-Pd complex serves not only to promote generation of chiral π-allyl-palladium intermediates and induce the asymmetry of the reaction, but also depress the background reaction.

Chiral Phosphine Ligands of COAP and SKP Switched Regiodivergent Asymmetric Allylic Alkylation of MBH Adducts.

The palladium-catalyzed highly regioselective asymmetric allylic alkylation of 3'-indolyl-3-oxindole derivatives with Morita-Baylis-Hillman (MBH) carbonates was developed to facilely construct chiral 3,3'-bisindole derivatives under mild reaction conditions. The regioselectivity (α/γ) of MBH carbonates was efficiently switched in the presence of chiral oxalamide phosphine or spiroketal-based diphosphine/Pd(0) complexes as a chiral catalyst. A series of multifunctional 3,3'-bisindole derivatives with all-carbon quaternary stereogenic centers were obtained in high yields with good to excellent enantio-, diastereo-, and regioselectivity. The present process is endowed with some salient features such as broad substrate scope, N-protecting group-free, excellent stereoselectivity, as well as adjustable regioselectivity.

COAP-Pd Catalyzed Asymmetric Allylic Alkylation of Azlactones with MBH Carbonates: Access to Unnatural α-Quaternary Stereogenic Glutamic Acid Derivatives.

A palladium-catalyzed regioselective and asymmetric allylic alkylation of azlactones with MBH carbonates has been developed with chiral oxalamide-phosphine ligands. The corresponding reaction afforded a range of optically active γ-arylidenyl glutamic acid derivatives bearing an α-chiral quaternary stereocenter in good yields with excellent linear regio- and high enantioselectivity. This protocol furnishes an alternative approach for the construction of enantio-enriched unnatural α-amino acid derivatives.

Genome Sequencing and Analysis Reveal Potential High-Valued Metabolites Synthesized by Lasiodiplodia iranensis DWH-2.

Lasiodiplodia sp. is a typical opportunistic plant pathogen, which can also be classified as an endophytic fungus. In this study, the genome of a jasmonic-acid-producing Lasiodiplodia iranensis DWH-2 was sequenced and analyzed to understand its application value. The results showed that the L. iranensis DWH-2 genome was 43.01 Mb in size with a GC content of 54.82%. A total of 11,224 coding genes were predicted, among which 4776 genes were annotated based on Gene Ontology. Furthermore, the core genes involved in the pathogenicity of the genus Lasiodiplodia were determined for the first time based on pathogen-host interactions. Eight Carbohydrate-Active enzymes (CAZymes) genes related to 1,3-ß-glucan synthesis were annotated based on the CAZy database and three relatively complete known biosynthetic gene clusters were identified based on the Antibiotics and Secondary Metabolites Analysis Shell database, which were associated with the synthesis of 1,3,6,8-tetrahydroxynaphthalene, dimethylcoprogen, and (R)-melanin. Moreover, eight genes associated with jasmonic acid synthesis were detected in pathways related to lipid metabolism. These findings fill the gap in the genomic data of high jasmonate-producing strains.

High production of jasmonic acid by Lasiodiplodia iranensis using solid-state fermentation: Optimization and understanding.

BACKGROUND: Jasmonic acid (JA) is a plant hormone involved in regulating developmental and growth controls as well as photosynthesis. In addition, this hormone protects the plant against insects and has good applications in agriculture, the flavored industry and other fields. Filamentous fungus generally produces JA using liquid static culture. In the present study, a solid-state fermentation (SSF) method is developed for high production of JA using Lasiodiplodia iranensis. MAIN METHODS AND MAJOR RESULTS: By selecting the solid substrate and optimizing the initial water content, inoculum volume, loading volume and other culture conditions, the maximum JA yield reached 5306.38 mg kg-1 when fermented for 12 days in a petri dish containing a medium with crushed wheat as the solid substrate and 75% initial water content. The logistic and Luedeking-Piret models were used to characterize the relationship between microbial growth and product synthesis in the SSF process, and the maximum JA production is predicted to be 5263.23 mg kg-1 , which is close to the experimental value. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) is used to examine the metabolic changes that develop during fermentation. The results indicate that JA biosynthesis occurs in the α-linolenic acid metabolic pathway, of which 13(S)-HpOTrE is a key intermediate metabolite and both 13(S)-HOTrE and traumatic acid are byproducts of the branches of its synthesis. CONCLUSIONS AND IMPLICATIONS: The results of this study provide a method for obtaining high JA yields by SSF, and offer new insights for understanding the production of JA by fungal fermentation.