Syntheses of diarylethenes by perylene-catalyzed photodesulfonylation from ethenyl sulfones
Diarylethenes were obtained from the corresponding ethenyl sulfones by photocatalyzed desulfonylation using UV or blue LEDs. When perylene and i-Pr2NEt were used as a photocatalyst and a sacrificing reagent, respectively, this desulfonylation proceeded smoothly to afford the desired ethenes with the functional groups such as chloro, alkoxy and heteroaromatic rings remaining untouched. The use of a flow photoreactor enabled this desulfonylation to proceed more rapidly to finish in an hour of residence time.
(Chemical Equation Presented) The first asymmetric total synthesis of antiochic acid using bioinspired polyene cyclization strategy is described. Both good yield and good asymmetric induction were obtained.
Zhao, Yu-Jun,Loh, Teck-Peng
supporting information; experimental part
p. 2143 - 2145
(2009/05/27)
Tryptamine-based human β3-adrenergic receptor agonists. Part 3: Improved oral bioavailability via modification of the sulfonamide moiety
The continued SAR investigation of tryptamine-based human β3-adrenergic receptor (AR) agonists is reported. Prior efforts resulted in the identification of 2 as a potent β3-AR agonist. Further modification of the left side arylsulfonamide portion in 2 provided compounds with good cell permeability, which have potent agonistic activity for β3-AR. Cinnamylamine analog 16i exhibited an excellent agonistic profile in vitro and good oral bioavailability in rats.
Double elimination protocol for convenient synthesis of dihalodiphenylacetylenes: Versatile building blocks for tailor-made phenylene-ethynylenes
Dihalodiphenylacetylenes are conveniently synthesized by a double elimination reaction of β-substituted sulfones which are readily obtained from halogen-substituted benzyl sulfone and benzaldehyde derivatives. Halogens can be incorporated at any desired positions in the diphenylacetylene skeleton simply by choosing the substitution position of the halogen on the aromatic rings of the starting compounds. The diphenylacetylenes with different halogen substituents thus obtained undergo sequential carbon-carbon bond formations due to the different reactivities of the halogens. Thus, various moieties can be incorporated on the diphenylacetylene skeleton at whichever positions so that a variety of tailor-made phenylene-ethynylenes with regulated structure and composition could be designed.
Sulfoximine version of double elimination protocol for synthesis of chiral acetylenic cyclophanes
A new strategy for constructing enantiopure acetylenic cyclophanes is described on the basis of one-pot double elimination reaction starting from dialdehydes and bis(sulfoximine)s. In this case, the conventional sulfone protocol affords poorer yields of t