Langduin C, a novel dimeric diterpenoid from the roots of Euphorbia fischeriana

Langduin C, a novel dimeric diterpenoid, was isolated from the roots of Euphorbia fischeriana and its structure was established by spectral data and single-crystal X-ray diffraction analysis.     

Synthesis of phenanthro[1,2-d]azepine derivatives containing a new heterocyclic system from the aporphine alkaloid glaucine

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A new abietane diterpenoid from the roots of Tripterygium regelii

A new abietane diterpenoid, tripterregeline A (1), together with six known diterpenoids (2–7), were isolated from the roots of Tripterygium regelii. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparison with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1–7 showed significant inhibitory effects against various human cancer cell lines with IC₅₀ values ranging from 0.58 to 21.06 μM.     

Synthesis of 4H-1,3-benzoxazin-4-ones from 2,2-diazidobenzofuran-3(2H)-ones

Benzoxazine derivatives are useful building blocks and display various biological activities. We serendipitously discovered and subsequently developed a new one pot method for the synthesis of 2-(dimethyl amino)/2-morpholino/2- (piperidin-1-yl)-4H-benzo[e][1,3]oxazin-4-ones from corresponding substituted 2,2-diazidobenzofuran 3(2H) - ones and N-formyl dimethyl amine (DMF)/N-formylmorpholine/N-formylpiperidine using m-CPBA at 100?°C in moderate to good yields. We also demonstrated the utility of 4H-benzoxazines for the synthesis of other medicinally important compounds such as 2-hydroxyphenyl substituted 1,2,4-triazoles, unsymmetrical 1,3,5-triazines, and 1,2,4-oxadiazoles.     

Highly selective BODIPY-based fluorescent probe for Zn2+ imaging in plant roots

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Biphenyl ether and biphenyl quinolizidine lactone alkaloids from Heimia salicifolia

Three new biphenyl ether quinolizidine lactone alkaloids (1–3) and 13 new biphenyl quinolizidine lactone alkaloids (4–16) were isolated from Heimia salicifolia (Lythraceae) together with seven known alkaloids. Their structures were determined by spectroscopic analyses and chemical conversions.     

Gasification of metal-containing coals and carbons via their reaction with carbon dioxide

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Novel ent-kaurane dimers from Isodon rubescens var. rubescens

Three novel asymmetric ent-kaurane dimers xindongnins M-O (1-3) were isolated from Isodon rubescens var. rubescens. Their structures were elucidated by spectroscopic methods including 2D NMR analysis. The relative stereochemistry of 1 was determined by single crystal X-ray diffraction, which also confirmed the unique linkage of a single carbon-carbon bond between the two subunits of this dimer. A biogenetic pathway was proposed for the formation of these dimers.     

Self-condensation of N-substituted (4H-thieno[3,2-b]-pyrrol-5-yl)methanols into bis(thienopyrrolyl)methanes

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An asymmetric ent-kauranoid dimer from Isodon rubescens var. lushanensis

A novel asymmetric ent-kauranoid dimer, lushanrubescensin J (1), was isolated from Isodon rubescens var. lushanensis. Its structure was elucidated by the spectroscopic evidences. The stereochemistry was confirmed by the single crystal X-ray diffraction of its tetraacetate. Compound (1) exhibited potent inhibitory activity against K562 cells with IC₅₀ = 0.93 μg/mL.     

Studies on the effects of doping cesium metal(III) halides of the type Cs3MIII2X9 (MIII = Sb or Bi, X = Cl or Br)

A series of compounds, Cs₃M^III₂X₉ (M^III = Sb and Bi, X = Cl or Br) are doped with impurity ions (Ba²⁺, Ca²⁺, Sn²⁺, Pb²⁺, Mg²⁺, Fe²⁺, Tl³⁺, In³⁺, Se⁴⁺). Lattices doped with Sn(II), Pb(II) and Se(IV) are colored. Sn-119m Mössbauer data are consistent with the donation of Sn-5s electron density from tin(II) to a conduction band to give a pseudo-tin(IV) electronic environment.     

Magnesium-substituted calcium phosphate bone cements containing MgO as a separate phase: synthesis and in vitro behavior

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3,4-Epoxyperfluorooxolane in the synthesis of new fluorine-containing furo[3,4-b]quinoxaline derivatives

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A new synthetic route to chiral 3-aryl-5-ethyl-1,4,2-oxazaphosphorines

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Diterpenoids from the fruits of Rhododendron molle, potent analgesics for acute pain

Rhododendron molle G. Don is one of the most potent traditional Chinese medicines for pain relief. Prior investigations have shown that Rhododendrons are rich sources of terpenoids. In our continuing efforts to identify structurally unique and biologically interesting diterpenoids, the fruits of R. molle were collected from Guangxi Province. A chemical study was carried out on the EtOH extract, which led to the isolation of 18 diterpenoids including 12 new compounds. The isolation and structural elucidation of new compounds 1–12, as well as the evaluation of the antinociceptive activities of these compounds were reported.     

Metal-free protocol for the synthesis of novel 6-(het)aryl-5-aryl-5H-imidazo[4,5-b][1,2,5]oxadiazolo[3,4-e]pyrazines

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Hainanmycin A,a cyclo-heptadeca macrolide bearing a cyclopentenone moiety from the mangrove-derived Streptomyces sp. 219807

A macrocyclic polyketide with novel carbon skeleton, namely hainanmycin A, was isolated from the mangrove-derived Streptomyces sp. 219807. This polycyclic compound featured a cyclo-heptadeca framework possessing a 5,6-disubstituted-4-hydroxy-2-pyrone moiety in conjunction with a 2-cyclopentenone residue. The structure was established by spectroscopic analyses, and the stereochemistry was determined by NMR chemical shifts calculations and time-dependent density functional theory (TDDFT) calculation of electronic circulardichroism (ECD). A possible biogenetic pathway for hainanmycin A was proposed.     

A novel direct catalytic production of p-xylene from isobutanol

A new one-step production of p-xylene (along with other liquid hydrocarbons) from isobutanol is catalyzed by zinc and chromium promoted micro-mesoporous MFI/MCM-41 composite (synthesized by hydrothermal-microwave method). The use of isobutanol of biogenic origin is in accordance with the principles of ‘green chemistry’.

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Highly efficient blue emission from boron complexes of 1-(o-hydroxyphenyl)imidazo[1,5-a]pyridine

Two boron complexes of 1-(o-hydroxyphenyl)imidazo[1,5-a]pyridine, which were named as BOHPIP, have been synthesized. These complexes exhibited blue emission in solution with high quantum yields (ΦFL?=?up to 0.71). In addition, 1-(o-hydroxyphenyl)imidazo[1,5-a]pyridine-BPh2 complex showed the strong blue emission even in the solid state (ΦFL?=?0.58).     

Daucus carota root enzyme catalyzed Henry reaction: A green approach

Enzyme from Daucus carota root catalyzed Henry reaction of substituted benzaldehydes and nitromethane in phosphate buffer of pH 7 at 28?°C to afford β-nitroalcohols in excellent yields (up to 94%).