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Serralongamines B (I) and D (IIb) exhibit significant inhibitory activity against foam cell formation in human macrophages.

Despite the widespread use of transition-metal catalysts in organic synthesis, transition-metal-catalyzed reactions of organosulfur compounds, which are known as catalyst poisons, have been difficult. In particular, the transition-metal-catalyzed addition of organosulfur compounds to unactivated alkenes remains a challenge. A novel gold-catalyzed hydrothiolation of unactivated alkenes is presented, which proceeds effectively to give the anti-Markovnikov-selective adducts in good yields and in a regioselective manner.

The total synthesis of (+)-tanikolide was accomplished by a traceless stereoinduction method using the key steps of a Rh(II)-catalyzed oxonium ylide formation–[2,3]-sigmatropic rearrangement and an N-heterocyclic carbene-catalyzed ring-expansion lactonization of tetrahydrofurfural. This synthetic route is applicable to the divergent synthesis of tanikolide analogues.

Iodoarene catalysts immobilized on magnetite (Fe3O4) were developed. The reactivity of catalysts 4 a and 4 b were similar to that of 4-iodophenoxyacetic acid (3) for the oxidation of 4-alkoxyphenols in the presence of Oxone® as a co-oxidant to give the corresponding p-quinones in high yields. In addition, 4 b was readily recovered by the use of an external magnet and was recycled up to eight times. This is the first example of a magnetic, nanoparticle-supported iodoarene catalyst.

An environmentally friendly oxidative cleavage of tetrahydrofuran-2-methanols to the corresponding γ-lactones using a catalytic amount of 2-iodo-N-isopropylbenzamide has been developed. The reaction of various tetrahydrofuran-2-methanols with the catalyst in the presence of Oxone® (2 KHSO5⋅KHSO4⋅K2SO4) as a co-oxidant in DMF at room temperature successfully affords the corresponding lactones in good to high yields, and recovery of the catalyst is readily accomplished using a reductive work-up. This method is notable because it enables the transformation of tetrahydrofuran-2-methanols to γ-lactones under mild conditions without the use of any toxic heavy metals.

The first total synthesis of an epidithiodiketopiperazine alkaloid, (+)-MPC1001B, was accomplished. This synthesis features a tetra-n-butylammonium fluoride mediated intramolecular aldol reaction for forming the 15-membered macrolactone ring, and the construction of an epidithiodiketopiperazine substructure through a stepwise sulfenylation reaction involving a novel trityl trisulfide (TrSSS)-group transfer.

The rearrangement of O-acylated oxidoles proceeds smoothly in the presence of chiral pyridine catalysts (I) to give oxindole derivatives in excellent yields with enantioselectivities up to 98%.

The total synthesis of (-)-isoschizogamine was accomplished, featuring the construction of the quaternary carbon center by the modified Johnson-Claisen rearrangement in basic media and the facile assembly of the key tetracyclic quinolone intermediate through a cascade cyclization. The characteristic cyclic aminal was constructed by late-stage C-H functionalization at the position adjacent to the lactam nitrogen using a combination of CrO3 and nBu4 NIO4 and subsequent Bi(OTf)3 -mediated cyclization.

The insertion reaction of isocyanides with thiocarbamates and selenocarbamates in the presence of a Pd(0) catalyst gives selectively 2-oxoethanimidothioates and -selenoates, respectively.

A simple protocol employing the chiral phosphine catalysts (I) is presented for the synthesis of diquinane, fused pyrrolidine, coumarine, and quinoline derivatives.

Achiral ethylenediamine forms chiral structures spontaneously when crystallized as the sulfate salt.

A simple and convenient reaction for the synthesis of isothioureas by Lewis acid-catalyzed insertion of isocyanides into the N—S bond of sulfenamides is developed.

Single crystals of the SrGeO3 high-pressure phase are prepared by hot pressing of the polycrystalline pseudowollastonite SrGeO3 (BN anvil press, 6 GPa, 1223 K, 1 h).

Commercial SiO is ball milled and vapor deposited to achieve an active Na-ion battery thick-film anode without the need for a binder or conductive additive.

A method for the stereoselective synthesis of alkylidenemalonates and related α,β-unsaturated esters by a hydrostannylation–cross-coupling process has been developed. Pd-catalyzed and radical hydrostannylation of propiolate derivatives stereoselectively provided α-alkoxycarbonyl (E)- and (Z)-vinylstannanes, respectively, which were then converted into alkylidenemalonates by the Stille coupling reaction. A one-pot process was also realizable for the Pd-catalyzed reactions.

2-Amino-4H-chromenes were synthesized in moderate to good yields by the reaction of o-quinone methides photochemically generated from o-(dimethylaminomethyl)phenols with malononitrile. This method was applicable to the synthesis of fluorinated chromenes that were difficult to obtain by other methods. In addition, o-(hydroxymethyl)phenols could be used for the reaction in the presence of tertiary amine bases.

Natural JBIR-108 is shown to be a mixture of the major diastereomer (Ia) and the minor diastereomer (Ib).

The dipyrrins (IV) obtained show a clear color change from red to blue when exposed to Broensted acids.

10-Methylacridinium is a stable aromatic cation exhibiting yellow-orange color and strong green fluorescence (FL), and can be used as a versatile building block in constructing a wide variety of novel π-electron systems. The dications with the two chromophores connected by a proper π spacer undergo reversible “dyrex” (dynamic redox) behavior, and C–C bond formation/cleavage is accompanied by their redox reactions. The prototype is biphenyl-2,2′-diylbis(10-methylacridinium), which exhibits electrochromic response with ON/OFF switching of FL during the reversible interconversion with the di(spiroacridan)-type electron donor. Slight structural alteration under the concept of “MFMS” (maximum function on the minimum skeleton) endowed the dyrex system with metal-binding or chiroptical properties, which could be modified by the redox reactions. Some of the di(spiroacridan) derivatives generated from bis(10-methylacridinium)s have extreme structural parameters, such as the greatest C–C bond length ever reported.

Decarbonylative rearrangement of seleno- and tellurocarbamates carrying an allenyl group on the nitrogen was found to proceed in the presence of a palladium catalyst to afford 3-chalcogeno-1-azadienes. This transformation may involve oxidative addition of Pd to a carbon–chalcogen bond, decarbonylation from a carbamoylpalladium unit (R2N-C(O)-PdChPh: Ch = Se or Te), Pd shift, and reductive elimination.

Synthesis of 2,2′-diamino-1,1′-biazulene derivatives 5 and 9–11 was established by copper-catalyzed homocoupling reaction of the corresponding 2-aminoazulenes 3 and 6–8. The palladium-catalyzed cro...

Versatile procedures for fluorocyclization of various tryptamine and tryptophol derivatives to obtain the corresponding 3a-fluoropyrrolo[2.3- b ]indoles and 3a-fluorofuro[2.3- b ]indoles, respectively were developed employing N -fluoro-2,4,6-trimethylpyridinium triflate (FP-T300) or Selectfluor™ as the electrophilic fluorinating agent. The use of NaHCO 3 for fluorocyclization was effective in improving the yield of acid-labile fluoropyrrolo(furo)indoles. Our procedures are especially useful for the synthesis of fluoropyrrolo(furo)indoles bearing a free NH indole group.

The catalyst can be recycled and reused at least 4 times without a significant loss in activity.

Polyhaloalkanes undergo radical 1,2-addition to olefins under thermal reaction conditions in the presence of NaOAc as an additive.

Treatment of primary and secondary alcohols with a catalytic amount of iodobenzamide in the presence of oxone yields the corresponding carbonyl compounds.

Six novel acyclic sulfides, named garlicnins L-1 (I), L-2, L-3, L-4 (II), E (III) and F are isolated which are able to suppress M2 macrophage activation.

Lanthanum trifluoromethanesulfonate is an effective single-component catalyst for synthesizing a variety of amides directly from esters and amines under mild conditions. Highly selective amidation of esters and amines, as well as catalyst-controlled amidation of esters, demonstrated the effectiveness of the catalyst system.

Over the past few decades, many studies have been conducted on ultralong C–C bonds (bond length greater than 1.7 A). This highlight review discusses the molecular design of ultralong C–C bonds and ...

The isolation of five novel natural sulfoxides as well as the elucidation of their relative structures are reported.

We synthesized π-extended donors for magnetic conductors that contain a stable 2,2,5,5-tetramethylpyrrolin-1-yloxyl radical, and cleared their structure and physical properties. We also discussed the conducting and magnetic properties of cation radical salts of the synthesized donor.

A TTP donor containing a stable PROXYL radical was synthesized to develop conducting-magnetic bifunctional materials and its structure and physical properties were investigated. Furthermore its cation radical salts were prepared and revealed their conducting and magnetic properties.

The preparation of multisubstituted indolines and carbazoles by a benzyne-mediated cyclization—functionalization sequence is described.

Pd-cataylzed treatment of allenes with activated vinyl selenides is found to result in efficient and regioselective formation of 2-selenomethyl-1,3-dienes.

[via [4 + 3] cycloaddition of (I) with an oxyallyl species generated from dibromopentanone (II) as the crucial step].

The title reaction leads to formation of isochromanone structures, whereas reductive work-up provides diols [cf.

Pyrrolines (I) react with arylaldehyde acetals (II) in the presence of a Lewis acid and base to give arylmethylidene pyrrolines (III).