Model synthetic studies towards palitantin total synthesis.

Studies towards the Total Synthesis of Asteriscanolide

Synthetic studies towards the tunicamycins and analogues based on diazo chemistry. Total synthesis of tunicaminyl uracil.

A synthetic approach to the tunicamycins, a complex family of nucleosides with potent antibiotic and antiviral activities is reported based on diazo chemistry. The corresponding precursors for the synthesis of tunicaminyl uracil derivatives, the non-stabilized diazo derived from 13 and the aldehyde derivative of uridine, compound 4, were prepared efficiently from commercially available D-galact...

Studies towards the total synthesis of lycoposerramine A. Synthesis of a model for the tetracyclic core.

Lycoposerramine A (1) is a pentacyclic alkaloid isolated in 2001 by Takayama and co-workers. A concise synthesis of a model compound 8 for the tetracyclic core of this natural product is described. Key steps include the desymmetrising free-radical cyclisation of compound 7 to give compound 18 and spirocyclisation of compound 26 to give compound 8. Earlier approaches using a novel high-yielding ...

Synthetic studies towards bottromycin

Thio-Ugi reactions are described as an excellent synthetic tool for the synthesis of sterically highly hindered endothiopeptides. S-Methylation and subsequent amidine formation can be carried out in an inter- as well as in an intramolecular fashion. The intramolecular approach allows the synthesis of the bottromycin ring system in a straightforward manner.

Synthetic Studies towards the Cadiolides

A novel laboratory synthesis of cadiolides was studied. Cadiolides are secondary metabolites from marine ascidians and tunicates, and they were found to have potent activity against Gram positive bacteria like Methycillin Resistant Staphylococcus Aureus (MRSA). Previous laboratory synthesis of Cadiolide B has been accomplished by 6 steps and with a 42% overall yield. However, this approach was ...