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Glycyrrhiza uralensis is the major plant source of licorice. This study was to identify bioactive compounds from the plant's leaves in order to make better use of its aerial part. An ethanol extract of the leaves was subjected to repeated chromatography to yield 15 compounds. The structures were determined to be three novel dihydrostilbenes, based on their various spectroscopic data-glycypytilbene A (1), glycydipytilbene (2), and glycypytilbene B (3)-and 12 known compounds, α,α'-dihydro-3,5,4'-trihydroxy-4,3'-diisopentenylstilbene (4), α,α'-dihydro-3,5,3',4'-tetrahydroxy-2,5'-diisopentenylstilbene (5), 6-prenyleriodictyol (6), 5'-prenyleriodictyol (7), 6-prenylquercetin-3-Me ether (8), 5'-prenylquercetin (9), 6-prenylquercetin (10), 6-prenylnaringenin (11), 3'-prenylnaringenin (12), sigmoidin C (13), 8-[(E)-3-hydroxymethyl-2- butenyl]-eriodictyol (14), and quercetin-3-Me ether (15). Most of these chemical constituents inhibited α-glucosidase activity, with the two prenylated quercetin derivatives (9 to 10) being the greatest active (IC50 < 4.0 µg/mL). Compounds 1, 3 to 4, 6 to 7, 9 to 12 impeded the growth of human hepatic stellate cells, with the prenylated flavonoids (6 to 7, 9 to 12) being more robust than their unprenylated counterparts. PRACTICAL APPLICATIONS: This study found that Glycyrrhiza uralensis leaves contain prenylated dihydrostilbenes and flavonoids with inhibiting effects on α-glucosidase and on the proliferation of human hepatic stellate cells, which should prompt the development of G. uralensis leaves for healthy products with anti-diabetic or liver fibrosis-preventing effects.

Twelve chemical constituents were identified from the Agriophyllum squarrosumseed (ASS). ASS contained large amounts of flavonoids, which were more concentrated in the seed coat. ASS‐coat (1 g) contained 335.7 μg flavonoids of rutin equivalent, which was similar to the flavonoid content in soybean (351.2 μg/g), and greater than that in millet, wheat, rice, peanut, and corn. By LC‐MS analysis, the major constituents in ASS were 3‐O‐[α‐L‐rhamnopyranosyl‐(1→6)‐β‐D‐ glucopyranosyl]‐7‐ O‐(β‐D‐glucopyranosyl)‐quercetin (1), rutin (4), quercetin‐3‐O‐β‐D‐ apiosyl(1→2)‐[α‐L‐rhamnosyl(l→6)]‐β‐D‐glucoside (2), isorhamnetin‐3‐O‐rutinoside (5), and allantoin (3), compared with isoflavonoids‐genistin (16), daidzin (14), and glycitin (18) in soybean. Among constituents in ASS, compounds 1, 2, 4, protocatechuic acid (8), isoquercitrin (11), and luteolin‐6‐C‐glucoside (12) potently scavenged DPPH radicals and intracellular ROS; strongly protected against peroxyl radical‐induced DNA scission; and upregulated Nrf2, phosphorylated p38, phosphorylated JNK, and Bcl‐2 in HepG2 cells. These results indicate that ASS is rich in antioxidant constituents that can enrich the varieties of food flavonoids, with significant beneficial implications for those who suffer from oxidative stress‐related conditions. This study found that A. squarrosumseed contains large amounts of antioxidative flavonoids and compared its chemical constituents with those of conventional foods. These results should increase the interest in planting the sand‐fixing A. squarrosumon a large scale, thus preventing desertification and providing valuable foods.

An efficient route for the synthesis of indeno[1,2-b]indoles as tetracyclic derivatives of indole bearing 2-oxo-1-pyrrolidine moieties through one-pot sequential or two-step iodine-catalyzed C–O activation and palladium-catalyzed C–H functionalization is reported.

1. Several groups have reported that melatonin produces a significant decrease in blood pressure in mammals and that pinealectomy in rats causes hypertension. The purpose of the present study was to investigate the effects of melatonin and bicuculline methiodide on the blood pressure of rats, both in the developing and fully developed stage of stress-induced hypertension (SIH). 2. Rats with SIH were generated by mild electric foot shocks for 15 days, after which tail arterial systolic pressure and plasma angiotensin (Ang) II levels were measured. The effects of melatonin injections (i.p. or i.c.v.) on mean arterial pressure (MAP) in rats with SIH were also determined. 3. Pretreatment with 1 mg/kg, i.p., melatonin significantly diminished the elevated tail arterial systolic pressure and plasma AngII levels caused by 15 days stress. The suppressive effects of melatonin were blocked by i.p. injection of 1 mg/kg bicuculline methiodide, an antagonist of the GABA(A) receptor. 4. Intraperitoneal (0.2, 0.5 and 1 mg/kg) or i.c.v. (0.15 and 1.5 microg/3 microL) injection of melatonin produced a dose-dependent lowering of MAP in rats with SIH. The antihypertensive response induced by melatonin was blocked by injection of both 1 mg/kg, i.p., and 1.5 x 10(6) microg/3 microL, i.c.v., bicuculline methiodide. 5. In conclusion, melatonin not only prevents increases in blood pressure during the developing stage of SIH, but can also reduce the blood pressure of rats that have already developed SIH. The antihypertensive effect of melatonin may be mediated by GABA(A) receptors through inhibition of plasma AngII levels.

An efficient TFA-catalyzed cleavage of C–N bonds in alkylation of indoles by tertiary enamides was described. A variety of bisindolylalkane derivatives, especially 3,3-bisindolylpropanoates, were expeditiously synthesized in good yields.

The two-step reaction sequence from (VI) via (VIII) to (IX) can also be conducted as a one-pot process with similar overall yields.

Optimized conditions are developed for the cross-coupling with symmetrical and unsymmetrical 1,3-dicarbonyl compounds.

The reaction which is conducted under-solvent free conditions leads to Markovnikov addition products.

γ-LiV2O5 nanorods with diameters of 30–40 nm and lengths of 0.4–2 μm have been synthesized by a simple solvothermal method at 160 °C using ethanol as a solvent, which also serves as a reducing agen...