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Leoligin, a tetrahydrofuran lignan isolated from the root of the edelweiss plant, was synthesised from veratraldehyde (2 mol), diethyl succinate and 2-methyl-(Z)-2-butenoic acid. Initially, veratraldehyde and diethyl succinate underwent a Stobbe condensation to yield a C6-C5 acid which, after esterification, was condensed with a second molecule of veratraldehyde to generate a 2,3,4-trisubsituted γ-butyrolactone intermediate. Two reduction steps yielded a triol, which was ring-closed with tosyl chloride to form a hydroxymethyl-tetrahydrofuran, esterification of which with 2-methyl-(Z)-2-butenoic acid generated leoligin.

The first total synthesis of the dihydrobenzofuran neolignan quiquesetinerviusin A and its related structure have been described. Phenolic coupling is the key step to constructing the dihydrobenzofuran skeleton with vanillin as the raw material. The hydroxyl group was protected with dihydropyran (DHP) and the ester group was reduced with diisobutylaluminium hydride (DIBAL-H) in order to obtain the crucial intermediate diol, which was then condensed with an acid ligand to give the desired compounds following removal of the protecting groups.

(E,E)-N,N-Dityramin-4,4′-dihydroxy-3,5′-dimethoxy-β,3′-bicinnamamide, a lignanamide isolated from Aptenia cordifolia, was synthesised from vanillin and tyramine. The key 8-5′-neolignan intermediate diacid was formed efficiently using oxidative coupling of the ferulic acid derivatives and the ring-opening reaction of a dihydrobenzofuran.

The first total synthesis of dilignan Boehmenan has been achieved. A biomimetic oxidative coupling of the ferulic acid methyl ester in the presence of silver oxide is the crucial step in the synthesis sequence, generating the dihydrobenzofuran skeleton. Hydroxyl group was protected with DHP and reducted with LiAlH 4 to afford the intermediate diol. The diol was condensated with the derivative of ferulic acid, then removed the protecting groups, to get Boehmenan. Meanwhile, a study on the ring-opening reaction of the intermediate dihydrobenzofuran neolignan under base conditions was described.

Cannabisin B, a naturally occurring lignanamide, has been synthesised for the first time in 15% overall yield. The convergent synthesis is based on the Stobbe reaction and Friedel–Crafts alkylation reaction as the C–C bond-forming steps to afford the skeleton of the lignanamide which was then condensed with 4-methoxyphenethylamine to obtain Cannabisin B.

A readily available chiral camphor-derived auxiliary was synthesised through a highly efficient and short general route. The Darzens reaction of the auxiliary with aldehydes in the presence of base gave glycidic esters with almost complete diastereocontrol and high yield.

The present study describes the performance of the HZSM-5 zeolite catalyst modified by Cu, Zn, Ga, La, P, Ag, and other ions for the conversion of methanol to aromatics in a fixed-bed reactor, and the influences of the system pressure and temperature on methanol aromatization are in discussion. The results show that the optimum single ion for the modification of catalyst was Zn or Cu. The optimum combined ions were Zn and Ga. The yield of aromatics could reach up to 66.6% on the catalyst modified with Ga2% and Zn10%.

A convenient method for the synthesis of lignanamide Cannabisin G, starting from the vanillin, was developed. The convergent synthesis was based on the Stobbe reaction as C-C bond-forming steps to give the skeleton of lignan, which was condensed with a derivative of tyramine to obtain synthetic Cannabisin G for the first time.

The total synthesis of threo-(±)-9,9-dibenzoylsecoisolariciresinol and its isomer based on two Stobbe reactions as C–C bond-forming steps used a protected vanillin and diethyl; succinate to give the skeleton of lignan, followed by reduction to afford threo- and meso-(±)-secoisolariciresinol Both were treated with benzoyl chloride to obtain the natural product threo-(±)-9,9-dibenzoylsecoisolariciresinol and Its isomer meso-(±)-9,9-dibenzoylsecoisolariciresinol for the first time.

A convenient method for the synthesis of sesquilignan threo- and erythro-(±)-divanillyltetrahydrofuran ferulate is described. The synthesis was based on a unified synthetic strategy involving two Stobbe condensations to give the skeleton of lignan, and then reduction reaction to form meso- and threo-(±)-secoisolanciresinol. meso- and threo-(±)-secoisolanciresinol were separated by flash column chromatography, followed by intramolecular reaction with TsCl to afford the key intermediate meso- or threo-(±)-shonanin, then condensation with ferulaic acid to obtain sesquilignan threo- or its analogue erythro-(±)-divanillyltetrahydrofuran ferulate.

Full details of the total syntheses of erythro-nordihydroguaiaretic acid, threo-(-)-saururenin and their analogues are presented. The syntheses were based on a unified synthetic strategy involving the Stobbe Reaction, alkylation to construct the skeleton of lignans and resolution of the threo- and erythro-isomers. The syntheses were achieved in eight to nine steps from simple aromatic precursors, and by this route 13 lignans were obtained. Among the synthesized lignans, seven lignans were natural products; moreover three of the seven natural products were synthesized for the first time. The effect of 13 lignans was examined on HIV Tat transactivation in human epithelial cells, HSV-1 gene and human leukemic, liver, prostate, stomach and breast cancer cell. Bioactivity results indicated that one product showed activity against the HIV gene and five compounds exhibited anti-HSV activity.

An efficient synthesis of dibenzylbutyrolactone lignans and their analogues has been developed. Based on a Stobbe condensation of piperonal or veratraldehyde with diethylsuccinate and alkylation with 3,4-methylenedioxybenzyl bromide to give the skeleton of the lignan. The (±)-diacid was resolved with quinine and the functional groups were transformed to obtain three benzylbutyrolactone lignans and seven analogues. Four natural lignans were prepared by this method, and five lignans were synthesised for the first time. The synthesised compounds were evaluated for anti-HIV, anti-HSV, and anti-tumour activities. Results showed that the dibenzylbutyrolactone lignans and their analogues were inactive against HIV Tat transactivation and HSV-1 in vitro, but some compounds displayed significant activity against MDA-MB-435 human breast cancer cell.

The asymmetric synthesis of the natural neolignan (1R,2S)-2-(4′-allyl-2′,6′-dimethoxyphenoxyl)-1-(4″-hydroxy-3″,5″-dimethoxyphenyl)propan-1-ol based on an asymmetric dihydroxylation as a key reaction using AD-mix-β to preparing the chiral threo-(1R,2R)-glycerol. The reaction, threo-alcohols were inverted by an SN2 reaction into erythro-(1R,2S)-isomers.

A synthesis of the tetrahydrofuran lignan (±)-agastinol, starting from the cheap Vanillin, has been developed based on Stobbe reaction with diethyl succinate to give the skeleton of lignan, which was then reduced to afford meso- and threo-(±)-secoisolanciresinol. threo-(±)-Secoisolanciresinol was treated with DDQ in acetic acid to give the 2-aryl tetrahydrofuran lignan, and which was then condensed with ferulic acid to give (±)-agastinol for the first time.

Full details of the asymmetric total synthesis of erythro-8-O-4′-neolignan, machilin C, and its analogue perseal A are reported. The synthesis was involved in the Sharpless dihydroxylation reaction that occurred with excellent asymmetric induction, and the Mitsunobu reaction which occurred with inversion of the absolute configuration from the threo to the erythro isomer. The synthesis was achieved from simple vanillin in eight to twelve steps.

A new methodology for the synthesis of the erythro -8- O -4’-neolignan Machilin C based on the Sharpless asymmetric dihydroxylation reaction and the Mitsunobu reaction as two key steps is described.

In the title compound, C19H15BrN2O, the dihedral angles formed by the imide group and the three benzene rings are 56.5 (2), 6.2 (4) and 55.7 (1)°. The mol­ecular structure and packing are stabilized by O—H⋯N, N—H⋯O and N—H⋯N inter­molecular hydrogen-bond inter­actions and C—H⋯π inter­actions.