The total synthesis of (±)-coriolin

The first total synthesis of (±)-coriolin from the tricyclo 6-4-5-fused ring photo-adduct through the key tricyclo 5-5-5-fused ring intermediate, 7,8,11 - trihydroxy - 1,4,4 - trimethyltricyclo[6.3.0.0^2,6]undecan - 3 - one, is described.     

First total synthesis of (±)-oxerine

Total synthesis of (±)-oxerine (1), a monoterpene alkaloid, starting from 3-bromopyridine (7) is described. The key reaction in this sequence is the samarium iodide (SmI₂)-mediated intramolecular cyclization of γ-ethynyl bromide (4).     

A stereocontrolled total synthesis of (±)-norzizanone

A stereocontrolled total synthesis of (±)-norzizanone 1 has been efficiently accomplished involving base-induced rearrangement of the mesylate 17 as the key step. Aryl participated intramolecular cyclisation of the bromophenol 11 provided the tricyclic dienone 12, which was stereoselectively converted into the mesylate 17.     

The total synthesis of (±) compactin and its natural (+) enantiomer

Total synthesis of (±) compactin $\text{12}$ and its natural (+) enantiomer has been achieved via a multistep sequence originating from butadiene and p-benzoquinone.     

A novel and efficient total synthesis of(±)-Cembrene-A

(±)-Cembrene-A,a highly active scent-trail pheromone,was first isolated from thetermite(Nasutitermes exitiosus)and its structure was established by using chemical and spectralmethods,Afterwards,it was also found in some plants and soft corals.In view of itsbiological activity,some total syntheses have been reported.It was reported that its dl-form showed the same order of activity as that of the natural pheromone,In previous work,     

Cyclisation of allyl silanes. Formal total synthesis of (±)-mesembrine

The intramolcular reaction of an α-acyl iminium ion with an allyl silane occurs under non acidic conditions to afford the key intermediate 8 for the sysnthesis of (±)-mesembrine 1 in a streospecific manner.     

Stereoselectivity in the organoiron-mediated synthesis of (±)-mesembrine

The preparation and structural characterisation of a 1-aryl-substituted electrophilic η⁵-cyclohexadienyliron complex with the correct functionalisation as a ‘C₁₂ building block’ for the synthesis of (±)-mesembrine establishes the accessibility of a flattened conformation to allow nucleophile addition ipso to the arene. The chirality relay in quaternary centre formation by nucleophile addition has been confirmed, and the product has been converted into the Sceletium alkaloid mesembrine.     

A simple and efficient synthesis of (±)-mesembrine

A simple and efficient synthesis of (±)-mesembrine 1 is described employing double Michael addition and as the key step in 18% overall yield.     

Total synthesis of (±)-fangchinoline

(±)-Fangchinoline was synthesized by condensation of (±)-1-(3-bromo-4-methoxy-benzyl)-2-methyl-6-methoxy-7-hydroxy-8-bromo-1,2,3,4-tetrahydroisoquinoline ( 2 ) and (±)-1-(4-hydroxy-benzyl)-2-methyl-6-methoxy-7-hydroxy-1,2,3,4-tetrahydroisoquinoline ( 3 ) in the presence of copper, pyridine and potassium carbonate.     

A convenient approach to the total synthesis of (±) 4-demethoxydaunomycinone

A convenient and most practical approach to the synthesis of (±) 4-demethoxydaunomycinone starting from 2-methylhydroquinone is described.     

Consecutive sigmatropic rearrangements in the enantioselective total synthesis of (−)-joubertinamine and (−)-mesembrine

Joubertinamine and mesembrine are two related alkaloids isolated from Sceletium plants. From the perspective of chemical synthesis, the major challenge posed by joubertinamine and mesembrine is undoubtedly the construction of the benzylic quaternary stereogenic center. We became intrigued by the prospect of applying successive sigmatropic rearrangements to build the key structural features of these alkaloids in enantioselective manner. In this article, we detail our results in this area, which include the enantioselective total synthesis of (−)-joubertinamine and (−)-mesembrine.     

A stereospecific synthesis of (±)-ferruginol

A stereospecific synthesis of (±)-ferruginol following the Robinson “ring extension” method has been described. The infra-red spectra of the benzoates of the synthetic and natural ferruginol are found to be identical.     

Synthetic studies on arene-olefin cycloadditions. ii. total synthesis of (±)-isocomene

The arene-olefin meta-photocycloaddition is shown to provide the basis for an effective and general approach to polyquinane natural products as demonstrated by the synthesis of (±)-isocomene (5) in five steps based on Z-2-bromo-2-butene and 2-bromotoluene.     

Highly stereocontrolled synthesis of [3.3.3] propellane sesquiterpenes. ( ± )-Modhephene and (±)-epimodhephene

Stereospecific total synthesis of (±)-modhephene (2) and (±)-epimodhephene (3) are reported. Conjugate addition of 1-trimethylsilyl-1-butyn-4-yl cuprate (BF₃-etherate catalysis) to bicyclic ketone 6, fluoride ion-promoted deblocking of the terminal acetylene, and ene reaction, gave tricyclic enone 11. Sequential Wittig methylenation, regiocontrolled epoxidation, and Lewis acid catalyzed isomerization afforded ketone 14 whose double bond relocation and Wolff-Kishner reduction led exclusively to 2. In a still shorter route to 3, 3-butenyl cuprate addition to 6 was utilized to gain access to 7. Thermolysis of this intermediate, methylenation, and double bond isomerization were found to deliver pure 3 successfully.     

A short and stereoselective synthesis of (±)-aristeromycin

A new Stereoselective three-step total synthesis of (±)-aristeromycin starting from readily available 1-hydroxymethyl-3-cyclopentene is described.     

The chemistry of vicinal tricarbonyls : A synthesis of (±)-slaframine and (±)-6-epi-slaframine

A synthesis of (±)-slaframine and (±)-6-epi-slaframine is described. The approach makes use of the intramolecular alkylation of an N-substituted 3-hydroxypyrrole-2-carboxylate ester.     

A simple synthesis of (±)1-Methyl benzofurocyciopentan-3-one

The synthesis of the title compound, a previously unreported tri-cyclic benzofuran analog, and the preparation of some of its derivatives is reported