Syntheses of 5′-O-desmethylterphenyllin and related p-terphenyls and their inhibitory activity of TNF-α release from RBL-2H3 cells

Rickenyls A–E, antioxidative terphenyls from the fungus Hypoxylon rickii (Xylariaceae, Ascomycota)

“…Several terphenyls were already reported with similar antioxidative activities, such as the curtisians A-D, thelephorin A, or sarcoviolin b (Liu, 2006;Ma et al, 2014). A variety of other biological activities for natural terphenyl derivatives was also described as exemplified by the topoisomerase I inhibitor echoside A (Deng et al, 2014), the TNF-a release inhibitor 5 0 -O-desmethylterphenyllin (Yajima et al, 2013), the leucomentins with neuroprotective activity (Lee et al, 2003), and the anticoagulant atromentin (Khanna et al, 1965). Due to the broad range of activities the natural function of terphenyls is mostly unclear.…”

A Concise Total Synthesis of (±)-Stepharine and (±)-Pronuciferine

“…As shown in Table 2 , we initially examined the reaction of aryl chloride 12 with boronic acid 13a under Yajima’s conditions–[Pd(OAc) 2 , SPhos and K 3 PO 4 in toluene]. 13c However, only a trace amount of desired product 11 was observed (Table 2 , entry 1). The reaction did not work either by change of base (e.g., NaOH or Na 2 CO 3 instead of K 3 PO 4 ) (entries 2, 3) or under Organ’s conditions (Pd 2 dba 3 ·CHCl 3 , Ipr·HCl and Cs 2 CO 3 in 1,4-dioxane) (entry 4).…”

Recent Applications of Phosphane-based Palladium Catalysts in Suzuki-Miyaura Reactions Involved in Total Syntheses of Natural Products

“…(OAc)2/RuPhos-catalyzed S.-M. reactions were used in the total synthesis of 4-O-methylhonokiol(256),[212] trienomycin A(257),[223] and virgatolide (258)[224] (Figure 11), and a Pd2(dba)3/JohnPhos-catalyzed S.-M. reaction was used to prepare a key intermediate of the enantioselective total syntheses of (-)-mersicarpine (259), (-)-leuconalam (260) and (-)-leuconoxine (261) (Figure 11),[215] three polycyclic Aspidosperma alkaloids. 4-O-Methylhonokiol (256) was isolated from Magnolia species[216a] and was found to exhibit higher antiinflammatory activity than honokiol (252).…”