Flavin Dependent Monooxygenase DszA Catalyzes C-S Bond Cleavage of Unnatural Dibenzothiophene Sulfones

The flavin dependent monooxygenase DszA converts dibenzothiophene sulfone (DBTO2) to 2-hydroxy[1,1'-biphenyl]-2-sulfinic acid (HBPS) through oxidative C-S bond cleavage. We report novel activity of DszA from Rhodococcus sp. IGTS8 on a library of DBTO2 derivatives, and establish that DszA can accept novel brominated and arylated dibenzothiophene sulfones. Significantly, we show that DszA acts on dinaphtho[2,1-b:1',2'-d]thiophene 7,7-dioxide to produce a 1,1'-bi-2-naphthol (BINOL) like scaffold. We anticipate that further development of DszA as a biocatalyst will overcome existing regio-and stereoselectivity limitations in synthetic approaches to BINOL compounds.