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The first asymmetric synthesis of obolactone utilizing a concise and efficient strategy is reported. The synthesis consists of 11 steps, starting from commercially available aldehyde 2 in 15% overall yield.

The strategic application of one-pot double allylboration and ring-closing metathesis reactions is utilized to accomplish concise and efficient asymmetric total syntheses of (+)-strictifolione and (6R)-6-[(4R,6R)-4,6-dihydroxy-10-phenyldec-1-enyl]-5,6-dihydro-2H-pyran-2-one. The total syntheses proceeded in only five and seven steps, respectively, from readily available 3-butenal and represents the shortest syntheses of (+)-strictifolione and (6R)-6-[(4R,6R)-4,6-dihydroxy-10-phenyldec-1-enyl]-5,6-dihydro-2H-pyran-2-one reported to date.

A concise, biomimetic total synthesis of the terpenoid skeleton (+)-chabraol is achieved via 6 steps from the chiral epoxide, which has involved an intramolecular Prins double cyclization to produce the bicycle[2.2.1] core of the natural product as the major step. The absolute configuration of natural chabranol is designated through the first asymmetric total synthesis.

The stereoselective syntheses of four diastereomers of natural 3,9,12-trihydroxycalamenene are presented. The syntheses have shown the utility of a framework of benzobicyclo[3.3.1] lactones, which are achieved by an intramolecular Friedel-Crafts-type Michael addition of [alpha],[beta]-unsaturated lactones.

An efficient and regioselective protocol is developed for preparing 5-hydroxy-2-isoxazolines, which is versatile synthons for isoxazles, [beta]-hydroxy oximes and [gamma]-amino alcohols. [beta]-Lactams embedded in the skeletons of bioactive natural products are prepared in two steps from [beta]-hydroxy oximes, which has provided a new strategy for the synthesis of this kind of compounds.

The development of a platinum-catalyzed tandem reaction involving enynyl ester isomerization and subsequent intramolecular [3 + 2] cyclization is described. This has provided an efficient approach to five-, six-, or seven-membered cyclic polyfunctional compounds.

An efficient total synthesis of (+)-aspergillide B is achieved, which has featured the C-glycosylation reaction for constructing the 2,6-trans-substituted pyran core, a highly effective four-step sequence without purification to produce the key intermediate and advantageous E-selective Julia-Kocienski olefination on a highly elaborate substrate. The synthesis has confirmed the revised structure of aspergillide B by Uenishi.

The first total synthesis of the 14-membered natural macrocyclic bislactone 4-keto-clonostachydiol, along with its enantiomer, is achieved in 13 steps with overall yields. The absolute configuration of 4-keto-clonostachydiol is revised as (5S,10S,13S).

The total synthesis of (-)-bitungolide F is described. The major steps have involved a Myers asymmetric alkylation to introduce the C6 methyl with proper stereochemistry, a Claisen-like cyclization to construct the [alpha],[beta]-unsaturated [delta]-lactone and a Julia-Kocienski olefination to assemble the conjugated diene moiety.

The efficient total syntheses of 11-[alpha]-methoxycurvularin and 11-[beta]-methoxycurvularin are described. The three-component linchpin coupling and intramolecular acylation reactions are key steps, in which the spectral data of 11-[alpha]-methoxycurvularin and 11-[beta]-methoxycurvularin are reversed with each other.

A simple and efficient synthesis of tribenzohexadehydro[12]annulene and related derivatives in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate is described. In the key step of the Sonogashira coupling reaction, the amount of CuI normally used could be reduced so that homocoupling is minimized.

A highly enantioselective asymmetric epoxidation for a beta-unsaturated esters using chiral ketone 2 as catalyst and Oxone as oxidant is presented. High ee's have been obtained for a number of trans-and trisubstituted substrates. The results described show that it is feasible for dioxiranes to effectively epoxidize electron-deficient olefins with high ee's.

An efficient metal-free Mizoroki-Heck type reaction of di- and tri-substituted alkenes with 2-chloro-dithiane has been developed under ambient pressure of air or using a relatively low loading of BF3⋅Et2O. This study represents a new environmentally friendly method for the syntheses of dithianyl-substituted alkene derivatives via a radical oxidative coupling process. [ABSTRACT FROM AUTHOR]

(-)-9-epi-Metazocine was synthesized through an Evans syn aldol reaction, ring-closing metathesis reaction and intramolecular radical cyclization. [ABSTRACT FROM AUTHOR]

Examines the asymmetric epoxidation of chiral oxazolidinone ketone catalyst. Synthesis of epoxides; Epoxidation of cis-olefins and terminal olefins; Absence of isomerization in acyclic systems.

The first total synthesis of (+)-cryptocaryanone A is described. The synthesis features a Mukaiyama aldol reaction, one-pot saponification/lactonization sequences, and TsOH-assisted dihydropyrone formation as key steps. [ABSTRACT FROM AUTHOR]

(+)-Neroplofurol was biomimetically synthesized in only two steps from natural (+)-nerolidol via Sharpless dihydroxylation and a cascade Shi epoxidation/epoxide ring-opening reaction. All carbons are derived from natural (+)-nerolidol and no protecting groups were utilized, making the synthesis atom-economical and highly efficient. The synthetic neroplofurol was proved to be the enantiomer of the natural one, according to 1H NMR, 13C NMR spectra and optical rotation value. The absolute configuration of natural neroplofurol was also deduced to be 3R,6S,7R,10S. [ABSTRACT FROM AUTHOR]

Discusses the enantioselective epoxidation of the alpha, beta-unsaturated esters by chiral dioxirane. Oxidant used for the epoxidation of the alpha, beta-unsaturated esters; Effectiveness of dioxiranes on the epoxidation of electro-deficient olefins with high enantioselectivities.