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Two new cyclic tetrapeptides, cyclo( l-Val- l-Leu- l-Val- l-Ile) ( 1) and cyclo( l-Leu- l-Leu- l-Ala- l-Ala) ( 2), and 15 known compounds, cyclo(Gly- l-Leu-Gly- l-Leu) ( 3), cyclo( l-Ser- l-Phe) ( 4), cyclo( l-Leu- l-Ile) ( 5), cyclo( l-Tyr- l-Phe) ( 6), cyclo(Gly- l-Trp) ( 7), cyclo( l-Leu- l-Tyr) ( 8), cyclo(Gly- l-Phe) ( 9), cyclo( l-Phe- trans-4-hydroxy- l-Pro) ( 10), cyclo( l-Leu- l-Leu) ( 11), cyclo( l-Val- l-Phe) ( 12), cyclo( l-Val- l-Leu) ( 13), cyclo( l-Ile- l-Ile) ( 14), cyclo( l-Tyr- l-Tyr) ( 15), turnagainolide A ( 16), and bacimethrin ( 17) were isolated from the fermentation broth of Streptomyces rutgersensis T009 obtained from Elaphodus davidianus excrement. Their structures were identified on the basis of spectroscopic analysis. Meanwhile, the absolute configurations of the amino acid residues of compounds 1 and 2 were determined by advanced Marfey method. Compound 3 was obtained from a natural source for the first time. The X-ray single crystal diffraction data of bacimethrin ( 17) were also reported for the first time. Compounds 1 - 17 exhibited no antimicrobial activities with the MICs > 100 μg/ml. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the anti-inflammatory effects and mechanism of isovitexin on ulcerative colitis mice and RAW264.7 cells. The results showed that isovitexin had strong antioxidant and anti-inflammatory effects, and could restore intestinal barrier integrity (p < 0.01). In addition, isovitexin inhibited the expression of MyD88, TLR4 and NF-κB p65 proteins. At the same time, isovitexin can inhibit the activation of MAPK/NF-κB signaling pathway in RAW264.7 cells. In conclusion, isovitexin has a protective effect on UC mice, and its improvement mechanism of UC might be related to MAPK/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Two new cyclic tetrapeptides (I) and (II) are isolated from the fermentation broth of Streptomyces rutgersensis T009 obtained from Elaphodus davidianus excrement together with 15 known compounds. [ABSTRACT FROM AUTHOR]

Cinnamic acid derivatives (CAs), which have proven to be versatile components, are present in abundance in biologically active natural products, and are widely used as intermediates in the manufacture of pharmaceuticals, and chemicals. The presence of cis - and trans -CAs created difficulties for natural product and organic synthetic studies. A highly efficient method that utilized iodine to entirely convert cis - CAs into their trans -forms was developed to solve this problem. The mechanism of study revealed this conversion occurred via an anti -diiodo intermediate. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "Highly Efficient Transformation of cis- to trans-Cinnamic Acid Derivatives by Iodine" by Z.-J. Li and others published in the journal "Tetrahedron Letters" in 2016.