STEREOSELECTIVE TOTAL SYNTHESIS OF(±)-4α(H)-EUDESMANE

The first stereoselective total synthesis of the biomarker(±)-4α(H)-eudesmane 1,starting from (-)-carvone in five steps,has been described.

The First Total Synthesis of Saurufuran B

First total synthesis of saurufuran B 1, a furanoditerpene, from （E, E）-farnesol 2 and citraconic anhydride 3 through thirteen steps is described. Our work involves two key steps： （1） High regioselective alkylation of 2-（tert-butyldimethylsiloxy）-4-methylfuran 6 with aUylic iodides 5 in the presence of silver wifluoroacetate and （2） Conversion of substituted 7-1actone 7 into furan derivative 8.

A STEREOSELECTIVE TOTAL SYNTHESIS OF (S)-(+)-γ-CURCUMENE

The stereoselective total synthesis of (S)-(+)-γ-curcumene starting from p-bromo-phenylmethyl ether via an asymmetric Grignard cross-coupling reaction in 45%ee optical yield was described.

ENANTIOSELECTIVE TOTAL SYNTHESIS OF 6R-(-)-MASSOIALACTONE

4'R, Z, 2-(4'-hydroxy-2'-nonenyl)-1,3-dioxane 2 which is an intermediate in the synthesis of chiral δ-lactones, has been syntheslzed from dlepoxide 3. Enantioselective total synthesis of 6R-(-)-massoialactone 1 has been achieved from 2 through 4 steps

The Total Synthesis of (±)-Hinesol and (±)-Agarospirol

A mild base-catalyzed retro-benzilic acid rearrangement of a proto-[2+2]photocycloadduct, formed in highly steroselective photoaddition of methyl 2,4-dioxo-pentanoate to 1,5-dimethyl-6-methylenecyclohexene, afforded a spiro[4, 5] decenedione from which hinesol and agarospirol were synthesized by means of reductive elimination of α-diketone and C1-homologation.

A FACILE TOTAL SYNTHESIS OF 6-PENTYL-α-PYRONE

A facile total synthesis of 6-pentyl-α-pyrone 1 has been described.The key step is the treatment of 2-furyl-pentyl-csrbinol 3 with NBS in aqueous tetrahydrofuran(THF).The overall yield is 34%.

A FACILE TOTAL SYNTHESIS OF (±)-SELINA-3,11-DIEN-9-OL

A ffcile tatal synthesis of (±)-selina-3. 11-dien-9-ol (1) has been described. The key step is the onepot reductive fragmentation of α,β-unsaturated p-tosylhydrazone and deduction of 9-carbonyl of 5 With sodium borohydride.

The First Total Synthesis of Five Elegan Type Natural Products

The first total synthesis of five linear diterpenes: eleganolone (1), eleganolone acetate (2), elegandiol (3), eleganonal (4) and epoxyeleganolone (5), was achieved from (E,E)-farnesol (6) via 4 to 6 steps. The key step was the alkylation reaction of silyl cyanide with allylic iodide.

A Total Synthesis of (±)-α-Chamigrene-3-one

The product. obtained by the photoaddition of terpinolene to methy 2. 4-dioxopentanoate. was subjected to cyclization to generate a spirocyclic compound having spiro[5. 5]. undecan structure, which was further transformed into α-Chamigrene-3-one by subsequent reactions.

Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester

The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction

Study on the Total Synthesis of Hainanolide (Ⅱ)──An Unexpected Hydroperoxide Containing Tricyclic Skeleton

An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed.

Studies on the Total Synthesis of Hainanolide(Ⅲ)-Unusual Diene Isomerization in a Diels-Alder Reaction

An unexpected diene isomerization of the triene acid 3 in the Lewis acid catalyzed intramolecular Diels-Alder reaction was observed

Studies on the Total Synthesis of Hainanolide(Ⅳ)-Revising the Stereochemistry of C_(2α)-H and Introducing the Two Hydroxy Groups at C_(3β),C_(4α) Positions

Tricyclic compound 6 was synthesized form compound 1 through sis steps, thus preblem of the stereochemistry of C2α-H being solved. The stereochemistry for introducing hydroxy groups at C3β and C4α positions in compound 1 was also described.

First total synthesis of (±)-abyssinoflavanone V

The total synthesis of （±）-abyssinoflavanone V was first achieved through C-prenylation, selective protection of phenolic hydroxyl group, aldol condensation, cyclization and deprotection starting from cheap 4-hydroxybenzaldehyde and 2,4,6- trihydroxyacetophenone, with total yield 24%. All structures of new compounds were confirmed by IR, 1^H NMR and MS.

First total synthesis of two nematicidal prenylated flavanones

The total synthesis of （＋）-8-（3-methylbut-2-enyl）-2-phenyl-2,3-dihydrochromen-4-one and （±）-2-（4-hydroxyphenyl）-8-（3- methylbut-2-enyl）-2,3-dihydrochromen-4-one was first achieved through C-prenylation, protection of phenolic hydroxyl group, aldol condensation, cyclization and deprotection starting from cheap benzaldehyde, 4-hydroxybenzaldehyde and 2-hydroxyace- tophenone, with total yield of 20 and 16.3%. All structures of new compounds were confirmed by IR, 1H NMR and MS. 2009 Jin Hui Yang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

A new isochroman-4-one derivative from the peel of Musa sapientum L.and its total synthesis

A new isochroman-4-one, 7,8-dihydroxy-3-methylisochroman-4-one was isolated from water soluble fraction of Musa sapientum L. Its structure was determined by spectroscopic evidences and its total synthesis has also been reported. The compound showed potent antihypertensive activity.

First total synthesis of (±)-puyanin and (±)-4'-O-methylbonannione

A facile approach for the first total synthesis of two naturally occurring geranylated flavonoids,（±）-puyanin 1 and（±）-4＇-O- methylbonannione 2 has been obtained with total yield 27%and 21%,respectively.The key steps were regioselective cyclization of geranylated trihydroxychalcone and regioselective geranylation of 2,4,6-trihydroxyacetophenone.

Stereoselective Total Synthesis of Chrysanthemol

Chrysanthemol, an active antiinflammatory sesquiterpene from Chrysanthemum indicum L., was synthesized in ten steps from R-(+)-carvone with an overall yield of 2.4%. The analytic data of the synthetic target compound was identical with that of natural chrysanthemol.