Synthesis of 5,5-Dimethyl-7-methoxy 4-oxatricyclo [4,3,1,03,7]decan-2-ones

Two new synthetic routes for the preparation of the title compound and its 3-substituted derivatives, a novel ring system present in morellin and other related natural products, are reported from the readily available dihydroanisoles

Synthetic studies on morellin. Part 4: Synthesis of 2,2-dimethyl- 12-[3-methylbut-2-enyl]-2H,6H-pyrano[3,2-b]xanthen-6-one

A new synthesis of 2,2-dimethyl-12-[3-methylbut-2-enyl]-2H,6H-pyrano[3,2-b]xanthen-6-one (7) is described from 1,3-dihydroxyxanthone and involved the preparation of a linear dihydropyranoxanthone (26), its conversion into the pyranoxanthone (14) and its prenylated derivative (31) followed by a Claisen rearragement leading to the target substrate (7)

Synthesis based on cyclohexadienes .23. Total synthesis of 5-epi-pupukean-2-one

A new strategy for the construction of the isotwistane skeleton is reported from easily available cyclohexadienes which involves stereoselective alkylation of a bicyclooctenone derivative and a decarboxylative 5-exo-trig radical cyclisation as the key steps in the total synthesis of 5-epi-pupukean-2-one

A Simple One Pot Synthesis of 1-Aryltetralins

Synthesis of 1-aryltetralins is described by the Fridel-Crafts arylation of 1-tetrols with phenol

A novel anion induced cope rearrangement

1-Hydroxy-3-methoxy-4-(3-methylbut-2-enyl)xanthen-9-one undergoes an unusual Cope rearrangement in the presence of a base. A mechanism involving a p-dienone intermediate for this transformation is proposed

An Expedient Route to the Preparation of Key Intermediates for the Total Synthesis of Aphidacolin, Stemodin and Oryzalexin S∗1S^{*1}

A strategy for the construction of tricyclo[6.3.1.0(1.6)]dodecane and tricyclo[7.2.1.0(1.6)]dodecane carbon skeleton present in several complex diterpenes is describe

Synthesis based on cyclohexadienes .24. A new total synthesis of pupukean-2-one and a facile entry to copa and ylanga type sesquiterpene skeletons

A novel tandem 5-exo-trig allyl and 3-exo-trig radical cyclisation and rearrangement to copa and ylanga type sesquiterpene skeletons from easily prepared cyclohexadienes is reported, A new total synthesis of pupukean-2-one 8, which belongs to a novel class of sesquiterpenes, involving a 5-exo-trig allyl radical cyclisation as the key step is also reported

Strategies of synthesis based on dihydrobenzenes

1-Methoxycyclohexa-1,4-dienes are readily available from the metal-ammonia-alcohol reduction of aromatic ethers. The use of these dihydrocompounds in the synthesis of a variety of natural products is reviewed

Synthesis Based on Cyclohexadienes .11. A A new total synthesis of (±)-norprezizanone

Acid catalyzed rearrangement of endo 1-methoxytricyclo[6.2.2.0(3,8)]dodec-2-en-10-ol 8c afforded the ketone 9 which has been transformed into (+/-)-norprezizanone 19 thus completing a formal synthesis of (+/-)-zizaene. A key step in this strategy is a stereospecific 1,4-addition of a methyl grou