ABSTRACT
The total synthesis of (+)-cyperolone, an eudesmane-derived sesquiterpenoid from Cyperus rotundus, is described. The de novo synthesis was accomplished via a 15 step sequence starting from (R)-(-)-carvone. The synthetic route features a platinum-catalyzed cycloisomerization to rapidly construct the bicyclic core from a 3-silyloxy-1,5-enyne intermediate.
Subject(s)
Sesquiterpenes/chemical synthesis , Terpenes/chemical synthesis , Catalysis , Cyclization , Cyclohexane Monoterpenes , Cyperus/chemistry , Isomerism , Molecular Structure , Monoterpenes/chemistry , Platinum/chemistryABSTRACT
An efficient and versatile synthesis of chiral tetralins has been developed using both inter- and intramolecular Friedel-Crafts alkylation as a key step. The readily available hydronaphthalene substrates were prepared via a highly enantioselective metal-catalyzed ring opening of meso-oxabicyclic alkenes followed by hydrogenation. A wide variety of complex tetracyclic compounds have been isolated with high levels of regio-, diastereo-, and enantioselectivity.
Subject(s)
Naphthalenes/chemistry , Tetrahydronaphthalenes/chemical synthesis , Alkylation , Molecular Structure , Stereoisomerism , Tetrahydronaphthalenes/chemistryABSTRACT
An efficient and versatile synthesis of cis-hexahydrobenzophenanthridines starting from readily available tetralins has been developed using an intramolecular Friedel-Crafts alkylation as a key step. The substrates were prepared via a highly stereocontrolled rhodium-catalyzed ring-opening reaction of meso-oxabicyclic alkenes and a hydrogenation sequence. Thus, a wide variety of complex tetracyclic compounds have been isolated with a high level of regio-, diastereo-, and enantioselectivity.
Subject(s)
Alkynes/chemistry , Siloxanes/chemistry , Cyclization , Molecular Conformation , Molecular Structure , StereoisomerismABSTRACT
Using synthetic functionalized analogues of pyochelin, a siderophore common to several pathogenic Pseudomonas and Burkholderia species, four fluoroquinolone-pyochelin conjugates were efficiently synthesized and evaluated for their biological activities.
