First total synthesis of （±）-malaysianone A and （±）-tanariflavanones B

A concise approach for the frst total synthesis of two naturally occurring flavanoids,（）-malaysianone A（1）and（）-tanariflavanones B（2）,has been accomplished with total yields of 12.9%and 10.4%,respectively.The key steps were regioselective deprotection and regioselective synthesis of 5-formaldehyde-8-hydroxy-2-[40-methyl-30-penteneyl]-dihydro-1-benzopyran（8）.     

An enantioselective formal synthesis of （-）-thujopsene

Dihydromayurone （3）, a key intermediate to synthesize （-）-thujopsene （1）, was efficient enantiocontrolled synthesized from （＋）-dihydrocarvone through 9 steps in an overall yield of 19.3%. The key step was the Simmons-Smith reaction.     

Formal synthesis of（＋）-tashiromine and study toward the total synthesis of（＋）-stemoamide

An effcient formal synthesis of（＋）-tashiromine was achieved by employing an intermolecular asymmetric Mannich-type reaction as the key step.Concurrently,a novel approach toward the total synthesis of（＋）-stemoamide through dyotropic rearrangement of 3,4-cis-b-lactone was also explored.     

A practical synthesis of （-）fosfomycin from its enantiomer

（＋）-cis-（1S, 2R）-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into （-）fosfomycin by a seven-step procedure. The esterification of the dihydroxyphosphonic intermediate was the key step. The title compound was obtained in good yield and its optical purity was up to the medicine quality standard of Chinese Pharmacopoeia.     

An improved synthesis of （-）-7-isopropyl-cis-1-amino-2-indanol the chiral auxiliary for 6π-azaelectrocyclization

(-)-7-Isopropyl-cis-1-amino-2-indanol, a key chiral auxiliary and ligand in the highly stereo-selective asymmetric 6π-azaelectrocyclization, has been prepared previously by two methods. Each however involved using of one extreme condition, i.e. high temperature or high pressure, for the respective reaction. A modified reaction route employed mild condition for synthesis was presented in this report.     

Stereoselective Synthesis of （Z）-α-Bromovinylstannanes and （E）-α-Iodovinylstannanes via Hydrozirconation of Alkynylstannanes

Alkynylstannanes 1 react with Cp2Zr(H)Cl(Cp=η^5-C5H5) giving (Z)-α-stannylvinylzirconium complexes 2, which are trapped with NBS or iodine in THF at 0℃ to stereoselectively afford (Z)-α-bromovinylstannanes and (E)-α-iodovinylstannanes 3, respectively.     

A facile stereospecific synthesis of （Z）-2-sulfonyl-substituted 1,3-enynes via Sonogashira coupling of （E）-α-iodovinyl sulfones with 1-alkynes

(E)-a-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2- sulfonyl-substituted 1,3-enynes 3 in high yields.     

Stereoselective Synthesis of （E）-1, 3-Enynyl Bromides via Pd／Cu-cata-lyzed Cross-coupling Reaction of （Z）-α-Bromovinylstannanes

(Z)-α-Bromovinylstannanes undergo the cross-coupling reaction with alkynyl iodides in the presence of Pd(PPh3)4 and CuI in THF at room temperature to afford stereoselectively (E)- 1, 3-enynyl bromides in good yields.     

Stereoselective Synthesis of （Z）-5-（Trideca-4-enyl）resorcinol and Gibbilimbols A-D

(Z)-5-(Trideca-4-enyl)resorcinol (1) and gibbilimbols A-D(2-5) were synthesized in 47%-60% yields over 6 steps from commercially available starting materials. The Wittig reaction of various alkyl phosphonium bromides with appropriate aldehydes in the presence of potassium tert-butoxide (t-BuOK) in anhydrous THF solution at room temperature served as the key step, and the result showed that only (Z)-configuration olefins were formed by this procedure. The synthesis of the (Z)-5-(trideca-4-enyl)resorcinol (1) was reported for the first time.     

A one-pot stereoselective synthesis of 1,4-dienyl selenides by hydrostannylation-Stille tandem reaction of acetylenic selenides with Bu_3SnH and allylic bromides

1,4-Dienyl selenides can be stereoselectively synthesized in one pot under mild conditions in good yields by the palladiumcatalyzed hydrostannylation of acetylenic selenides, followed by Stille coupling with allylic bromides.     

Stereoselective total synthesis of (±)-7-deoxy-trans-dihydronarciclasine, a potent antineoplastic phenanthridone alkaloid

A short and efficient stereoselective total synthesis of (±)-7-deoxy-trans-dihydronarciclasine, a highly potent antineoplastic agent and constituent of the Amaryllidaceae alkaloids, is described. Starting from a known arylcyclohexylamine-type precursor 6, the C-ring with the required stereochemistry is constructed using a chemo- and stereoselective enone reduction (NaBH₄/CaCl₂ system) and a Mitsunobu reaction. For the B-ring closure, the Banwell modification of the Bischler-Napieralski reaction was applied.     

A formal synthesis of (−)-swainsonine from a chiral aziridine

A formal synthesis of enantiomerically pure (−)-swainsonine was successfully achieved using intramolecular cyclization of the amino alcohol 4 which was derived from a readily available 1-(R)-α-methylbenzylaziridine-2-carboxylic acid (−)-menthol ester 6.     

A concise and convergent (formal) total synthesis of huperzine A

The first convergent synthesis of the tricyclic skeleton of huperzine A is described and includes, as the key step, an efficient regioselective intramolecular Heck reaction of 2-(tert-butyldimethylsilyloxymethyl)-6-(2-methoxy-5-bromopyridin-6-yl)methylcyclohex-2-enol.     

A stereoselective total synthesis of (−)-seychellene

A stereoselective total synthesis of the tricyclic sesquiterpene (−)-seychellene, starting from (R)-carvone via (R)-3-methylcarvone has been accomplished, employing a combination of intermolecular Michael addition-intramolecular Michael addition sequence, a stereoselective hydrogenation, and an intramolecular alkylation reaction.     

A concise stereoselective total synthesis of (+)-artemisinin

A protective group free, concise, and stereoselective total synthesis of (+)-artemisinin, starting from readily available (R)-(+)-citronellal, is described. Asymmetric 1, 4-addition, Aldol condensation, Ene reaction, regioselective hydroboration are the key steps involved in the total synthesis of the target molecule.     

A concise stereoselective formal total synthesis of the cytotoxic macrolide (+)-Neopeltolide via Prins cyclization

A convergent and highly stereoselective formal total synthesis of the naturally occurring, cytotoxic 14-membered macrolide neopeltolide has been achieved via two Prins cyclizations.     

A concise stereoselective total synthesis of Botryolide B

The first total synthesis of Botryolide B is described from easily accessible starting materials. The synthetic strategy involves Jacobsen resolution, Sharpless epoxidation, Swern oxidation, Yamaguchi reaction, and ring closing metathesis (RCM).     

Straightforward synthesis of indolizidine alkaloid 167B

The synthetic access to indolizidines, substituted in C-5 position, was reported with good diastereoselectivity. The strategy developed was based on a key step of Michael addition associated with a Clauson-Kaas condensation.