Five New Phenolic Compounds with Antioxidant Activities from the Medicinal Insect Blaps rynchopetera.

Five new phenolic compounds rynchopeterines A-E (1-5), in addition to thirteen known phenolics, were isolated from Blaps rynchopetera Fairmaire, a kind of medicinal insect utilized by the Yi Nationality in Yunnan Province of China. Their structures were established on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-MS, IR) along with calculated electronic circular dichroism method. Rynchopeterines A-E (1-4) exhibited significant antioxidant activities with IC50 values of 7.67-12.3 µg/mL measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Besides, rynchopeterines B (2) and C (3) showed mild cytotoxicity against tumor cell Caco-2 and A549.

Cytotoxicity of the Defensive Secretion from the Medicinal Insect Blaps rynchopetera.

Blaps rynchopetera Fairmaire has long been used as a folk medicine by the Yi and Bai ethnic groups in China to treat fever, cough, gastritis, boils, and tumors. In the present study, the cytotoxicity of the defensive secretion (TDS) of B. rynchopetera against AGS Caco-2, HepG2 U251 and Bel-7402 was tested, and the results revealed that TDS had potent cytotoxicity against testing cells with IC50 values of 45.8, 17.4, 53.6, 98.4 and 23.4 µg/mL, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis was employed to clarify the cytotoxic constituents in TDS of B. rynchopetera and five volatile compounds, including 2-ethyl-2,5-cyclohexadiene-1,4-dione (3, 31.00%), 1-tridecene (5, 28.02%), 2-methyl-2,5-cyclohexadiene-1,4-dione (2, 22.86%), hydroquinone (4, 1.33%), and p-benzoquinone (1, 1.01%), were identified. Chemical constituent investigation on TDS further supported the presence of 5 above compounds. A cytotoxic assay indicated that compounds 1, 2, 3 and 4 exhibited significant cytotoxicity against the testing cell lines, implying that benzoquinones and hydroquinone played important roles in the cytotoxicity of TDS of B. rynchopetera. TDS is a cytotoxic natural material and further studies investigating mechanisms and inhibitory activities on other cell lines is warranted.

[Two New Abietane Type Diterpenes from Pinecones of Pinus griffithii].

Objective: To study the chemical constituents from the pinecones of Pinus griffithii. Methods: The constituents were separated and purified with chromatographic methods,and spectroscopic analysis were employed for structural elucidation. Results: Two new abietane type diterpenes and seven known compounds were isolated from the pinecones of Pinus griffithii,and were identified as 15-hydroxy-7α-methoxy-abiet-8,11,13-trien-18-oic acid( 1),7α,13-dihydroxy-podocarpane-8,11,13-trien-18-oic acid( 2),7,12,13,15-tetrahydroxy-abiet-8( 14)-en-18-oic acid( 3),7ß,15-dihydroxy-abiet-8,11,13-trien-18-oic acid( 4),18-norabiet-8,11,13-trien-4,7,15-triol( 5),15-hydroxy-abiet-8,11,13-trien-18-oic acid( 6),7α-hydroxy-15-methoxy-abiet-8,11,13-trien-18-oic acid( 7),7α-hydroxypodocarpen-8( 14)-en-13-one-18-oic acid( 8), oleanolic acid( 9). Conclusion: Compounds 1,2 are the new abietane type diterpene,and all compounds are isolated from this plant for first time.

Blapsimidazolium A: A new imidazolium carboxylate derivative with anti-inflammatory activity from medicinal insect Blaps rynchopetera.

Blaps rynchopetera Fairmaire is a medicinal insect of Yi-nationality medicine used for a long time in Yunnan, China. In the present study, a new blapsimidazolium A (1), together with twelve known N-containing compounds (2-13), were isolated from this insect. The structures were elucidated by extensive spectroscopic analyses (1D and 2D NMR, HR-MS) and comparisons with the reported literature. Blapsimidazolium A was identified as racemic mixture by optical rotation and chiral analysis. Blapsimidazolium A (1) has a unique architecture containing an imidazolium carboxylate moiety. The results of molecular docking showed that blapsimidazolium A bound well to IL-1ß, IL-6 and iNOS. The racemates of (±)-blapsimidazolium A (1) exerted anti-inflammatory activity in LPS-stimulated THP-1 cells by significantly decreasing the production of the proinflammatory cytokines IL-1ß, IL-6 and iNOS. This is the first report describing the anti-inflammatory activity of this type imidazolium carboxylate derivative.