A chemoenzymatic total synthesis of the hirsutene-type sesquiterpene (+)-connatusin B from toluene

Lentinulactam, a hirsutane sesquiterpene with an unprecedented lactam modification

“…Therefore, the absolute configuration at C-1 was assigned as R-configuration and thus the absolute configuration of connatusin A (2) is 1R,2R,3R,7S,9R which is consistent with that previously reported for connatusin A. 12,13 Our findings supported the previously reported configuration for connatusins and confirmed that lentinulactam (1) Compounds 4 and 5 were assigned as 6-hydroxy-2,2-dimethylchroman-4-one (4), and 6-methoxy-2,2-dimethylchroman-4-ol (5) (Figure 1) by comparison of their HRESIMS and NMR data with those in the literature. 10,11 The nomenclature of compound 5 was incorrectly published by Rukachaisirikul et al 8 as 2,2-dimethyl-3-hydroxy-6-methoxy-4-chromanone.…”

“…Although only the relative configuration was reported, 8 total synthesis studies conducted later for both connatusins and claimed the confirmation of the absolute configuration (R at C-1). 12,13 In this context, we have repeated Mosher ester analysis using a different protocol.…”

Linear Triquinane Sesquiterpenoids: Their Isolation, Structures, Biological Activities, and Chemical Synthesis

“…Bon and co-workers showed great interest in the synthesis of the linear triquinane sesquiterpenoids. In 2010, they reported a chemoenzymatic total synthesis of (+)-connatusin B ((+)- 34 ) from toluene [ 73 ]. In this synthesis, the starting material employed the cis -1,2-dihydrocatechol ( 167 ), which was acquired in enantiomerically pure via the enzymatic dihydroxylation of toluene.…”

Realization of Photo‐Thermal Metathesis Under Microwave Irradiation Conditions: An Entry to Triquinane Frameworks

“…Their biological activity and stereochemical intricacies justify thier synthesis . In this context, capnellene ( 2 ), (+)‐connatusin ( 3 ), (−)‐complicatic acid ( 4 ), ceratopicanol ( 5 ), cucumin E ( 6 ), hypnophilin ( 7 ) (Figure ) represent selected synthetic targets. Several groups are engaged in design and synthesis of quinane‐based targets.…”