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Three new 3,4-seco-grayanane diterpenoids, neopierisoids D-F (2-4), and a new natural one, neopierisoid C (1), were isolated from the flowers of Pieris japonica. Their structures were elucidated on the basis of extensive spectroscopic analysis, including one and two dimensional (1- and 2D)-NMR, as well as high resolution-electron ionization (HR-EI)-MS.

A new method for the synthesis of secondary thiocarbamates from readily available isocyanides and thiosulfonates with broad functional group tolerance is reported. The reaction proceeds under mild reaction conditions in isopropanol and is catalyzed by inexpensive sodium iodide.

Hyperjapones A–E (1–5), novel terpenoid polymethylated acylphloroglucinols (TPAPs) with unusual architectures, were characterized from Hypericum japonicum. Their structures and absolute configurations were determined by comprehensive spectroscopic data and X-ray diffractions. Compound 1 was obtained as a racemic mixture and was separated by a column coated with cellulose tris(4-methylbenzoate) after attempts with various chiral materials. Compounds 1, 2, and 4 exhibited moderate antitumor activities in vitro.

A simple and novel synthesis of polytrisubstituted-2-pyridones derivatives by the reaction of enamino esters and diethyl ethoxymethylenemalonate has been reported. The method provides a rapid synthetic route for the construction of 2-pyridones under catalyst- and solvent-free reaction conditions in moderate-to-good yields.

Hypercohin K (1), the first polycyclic polyprenylated acylphloroglucinol possessing a unique spiro-fused cyclopropane ring, together with hyphenrone L (2) representing the most complex congeners featured with a hexacyclic core, was isolated from Hypericum cohaerens. The structure of 1 was elucidated by extensive MS and NMR spectroscopic data. The absolute configuration was defined by comparison of the experimental and calculated ECD. Compound 1 was evaluated for the inhibitory activities against acetylcholinesterase and four human tumor cell lines. (C) 2015 Elsevier Ltd. All rights reserved.

A new I2/CuO-promoted one-pot tandem strategy is presented for the synthesis of imidazo[1,2-a]pyridine derivatives which has a broad scope of substrates, including aryl methyl ketones, heteroaryl ketones, α,β-unsaturated methyl ketones, β-ketone esters, and substituted 2-aminopyridines.

Compounds (IV) containing cationic Ln24Zn4 cluster cores crystallize in the cubic space group Fmm with Z = 8 (single crystal XRD).

Substrates (I) with aroyls, esters and conjugated enones attached to the 5-position require two or more electron donating methoxy groups at the aryl ring to promote the reaction.

Multiple applications of isothioureas as fine chemicals (or their precursors) are known, but a general sustainable method for their synthesis was hitherto unavailable. We report a novel general approach towards S-alkyl and S-aryl isothioureas through a copper(I)-catalyzed three-component reaction between amines, isocyanides, and thiosulfonates. The formal synthesis of a superpotent sweetener further illustrates the applicability of our method.

Sevelamer, a phosphate-binding drug, is successfully used as catalyst in Knoevenagel reaction.

isolation, structure and cytotoxicity of two novel abietane diterpenoids, wardinol A (I) and B (II), along with five known diterpenoids

The compounds (IIIa)-(IIId) show more effective abilities for both title mentioned targets than the reference compounds Resv and ISL.

The title reaction allows the efficient synthesis of natural products such as eudistomins (IIIb) and (VIa), pityiacitrin (IIIe), and papaveraldine (IXb) as well as structurally related analogues.

A facile synthesis of enediones is achieved via copper-catalyzed coupling of 1,3-dicarbonyl compounds with 2-haloketones, 2-hydroxyketones, or methylcarbinols.

An I2/KOH synergistically promoted direct ring-opening aroylation of benzothiazoles with aryl ketones has been discovered. Aryl ketones were seen to act as carbonyl sources to construct 2-acylbenzothiazoles. This reaction could provide an example for the convergent integration of self-labor domino sequences based on an in situ cross-trapping strategy.

The heterocyclic skeleton is readily available in moderate yields without the need for any metal or base catalyst.

Substituted naphthalene derivatives are obtained by rearrangement aromatization of benzo[c]oxepines (I).

A series of 5-alkoxytetrazolo[1,5-c]thieno[2,3-e]pyrimidine derivatives were synthesized and their anticonvulsant and antidepressant activities were evaluated. Pharmacological tests showed that four of the synthesized compounds had weak anticonvulsant activity, while most of the compounds had excellent antidepressant activity. The most active compound was 5-(2,4-dichlorobenzyloxy)tetrazolo[1,5-c] thieno[2,3-e]pyrimidine, which decreased the immobility time by 51.62% at a dose of 100 mg/kg. The results of open-field tests of this compound indicated that it had no significant effects on the locomotor activity compared with the control group at the doses assayed in the forced swimming tests test. This means that the antidepressant activity detected in the FST for the compound is not the result of central nervous system stimulant properties, and further confirms its antidepressant-like effect.

A novel and convenient one-pot protocol for the synthesis of quinoxaline derivatives is developed starting from simple ketones and phenylenediamines.

A new, mild, and efficient method to prepare 3,6-disubstituted pyridazines and 6-arylpyridazinones is reported.

An I2–CF3SO3H synergistic promoted sp3 C–H bond diarylation protocol was developed for the synthesis of 2,2-bis(4-(dimethylamino)phenyl)-1-aryl ethanones. The reaction performed well in the absence...

An I2 promoted domino protocol was developed to construct 2-acylbenzothiazoles from simple and readily available aromatic ketones/unsaturated methyl ketones and o-aminobenzenethiols. The reaction proceeded smoothly under metal-free and peroxide-free conditions.

A novel and highly regioselective two-step homocoupling/cyclization procedure from easily available aryl methyl ketones and hydrazine hydrate was developed for the synthesis of methylthio-substituted pyridazines at room temperature. The method has remarkable advantages owing to the simple substrates, mild reaction conditions, ease of manipulation, good yields and high ­regioselectivity.

It is found that metal-free oxidation of styrenes, arylacetylenes, 2-hydroxylated aromatic ketones, and carbinols can provide phenylglyoxals.

A molecular I2-promoted sp3 C–H bond dual-(het)arylation protocol was developed for the synthesis of 2,2-bisindolyl-1-arylethanones. Through a logical design, three mechanism-different reactions (iodination, Kornblum oxidation, and Friedel–Crafts reaction) were assembled in a single reactor. A variety of 2,2-bisindolyl-1-aryl ethanones were synthesized from simple and readily available aryl methyl ketones and indoles. In the reaction, metal, base, and ligand were all avoidable.

Methylthio-substituted enediones are applied as mixtures of (E)/(Z)-isomers in the optimized reaction with primary or secondary amines.

A mechanism for the synthesis of polysubstituted oxazole derivatives (III) from methyl ketones (II), benzoin (I) and ammonium acetate is suggested.

The CoII/CoIII (9:1) mixed compounds (III) and the NiII compounds (V) are isostructural and crystallize in the monoclinic space group P21/m with Z = 2 (single crystal XRD).

α-Formyloxy and acetoxy ketones (III) and (V) are prepared from aromatic and unsaturated methyl ketones (I).

Indoles and 1,4-endiones undergo domino Friedel—Crafts alkylation/ Paal—Knorr cyclization to afford furanyl-indole derivatives.

An efficient method for the preparation of amides via a tandem Liebe/Haller—Bauer reaction is given.

The plants of genus Dipsacus, with a wide distribution in Europe, Asia, and Africa, have been used as medicinal agents to treat several diseases, including lime disease, fibromyalgia, bone fracture, and abortion, and especially the Alzheimer's disease and cancer. A large number of studies on plants of genus Dipsacus has revealed cytoprotective properties, inhibition of HIV-1 reverse transcriptase, antinociceptive, and antimicrobial effects, etc. This review compiles all chemical constituents isolated, mainly triterpenoids, iridoids, phenolics, and alkaloids, from the genus Dipsacus over the past few decades together with their structural features, biological activities, and structure-activity relationships.

A combinatory library of title compounds is designed by exploring the effect of the 6-cyclohexyl moiety in the 4-pyrimidinone series on the anti HIV-1 activity.

Four sesquiterpenes, structurally related to caryophyllene, cyclocaryophylla-4-en-8-ol, euphanginol, 14-hydroxy-4β,5α-epoxy-4,5-dihydrocaryophyllene and clovandiol, were isolated from whole plants of Euphorbia wangii . Their structures were elucidated by spectroscopic methods including 2D NMR techniques and by some chemical transformations. One of them is a new compound. This is the first investigation on sesquiterpenoids from the genus Euphorbia .

The roots of Ligularia intermedia yielded four benzofurans, a novel phenol derivative, 2-isopropenyl-6-acetyl-8-methoxy-1,3-benzodioxin-4-one, and three substituted geranyls, including two new hydroperoxide compounds, (E)-4-(6-hydroperoxy-3,7-dimethylocta-2,7-dienyloxy)-syringenin and (E,E)-4-(7-hydroperoxy-3,7-dimethylocta-2,5-dienyloxy)-syringenin. Structures were elucidated using chemical and spectroscopic methods.

Phytochemical inves tigation o f the whole plants of Artemisia arenaria affords one new ClIdcSIllL1n e sesqlliterpene, eudesm-5-ene-I~, 4a-dioll and ten known compounds, a-amyrin 2, ~ -amyrin 3 , ~s itostero l 4 , 4-hydroxyacetophcnone S, 5 , 7-dihydroxy-4 '-mcthoxyfl avanone 6 , 5-hydroxy-7 , 4'-d imcthoxy ll ava nonc 7 , 5. 6, 3'-trimethoxy fl avanone 8 , 5-hydroxy-7, 4' -dimethoxyfl avo ne 9 , 5-hydroxy-6, 7, 4' -trimcthoxy l'lava nnne 10 and sti gmasterol 11 . Their structures have been elucidated on the basis of spectroscopic mcthods.

The West Indian alcyonacean Pseudopterogorgia bipinnata (Verrill, 1864) is shown to contain a novel bisditerpenoid ether: biskallolide A (2). The structural assignment of 2 was mainly based on 1D and 2D NMR and MS spectral data and was further confirmed by synthesis. The 2-C-alkoxylation of furanopseudopteranes kallolide A (1) and isokallolide A (8) occurs spontaneously in some solvents and involves replacement of the C2 hydroxyl with an alkoxyl group to yield solvolysis products that display net retention of configuration. The facile solvolytic 2-C-acyloxylation of kallolide A was achieved readily under similar circumstances to afford kallolide A acetate (4) as the sole product. Mechanistic details in conversion of alcohols 1 and 8 into various solvolysis products, including dimeric ethers 2 and 9, were investigated in this study. Solvolysis of kallolide A and isokallolide A in [(18)O]-labeled solvent demonstrated that the C2 alkoxyl of the solvolysis products originated from the solvent, suggesting that these conversions may proceed through an S(N)1 mechanism with generation of a carbocation intermediate. The chemical structures of kallolide A derivatives 3-7and those of isokallolide A congeners 9-11 were established by detailed analysis of the spectral data.