573-12-6Relevant articles and documents
Facile synthesis of 1,2-dione-containing abietane analogues for the generation of human carboxylesterase inhibitors
Binder, Randall J.,Hatfield, M. Jason,Chi, Liying,Potter, Philip M.
, p. 79 - 89 (2018/03/06)
Recently, a series of selective human carboxylesterase inhibitors have been identified based upon the tanshinones, with biologically active molecules containing a 1,2-dione group as part of a naphthoquinone core. Unfortunately, the synthesis of such compounds is complex. Here we describe a novel method for the generation of 1,2-dione containing diterpenoids using a unified approach, by which boronic acids are joined to vinyl bromo-cyclohexene derivatives via Suzuki coupling, followed by electrocyclization and oxidation to the o-phenanthroquinones. This has allowed the construction of a panel of miltirone analogues containing an array of substituents (methyl, isopropyl, fluorine, methoxy) which have been used to develop preliminary SAR with the two human carboxylesterase isoforms. As a consequence, we have synthesized highly potent inhibitors of these enzymes (Ki 15 nM), that maintain the core tanshinone scaffold. Hence, we have developed a facile and reproducible method for the synthesis of abietane analogues that have resulted in a panel of miltirone derivatives that will be useful tool compounds to assess carboxylesterase biology.
Regiospecific oxidation of polycyclic aromatic phenols to quinones by hypervalent iodine reagents
Wu, Anhui,Duan, Yazhen,Xu, Daiwang,Penning, Trevor M.,Harvey, Ronald G.
experimental part, p. 2111 - 2118 (2010/04/26)
The hypervalent iodine reagents o-iodoxybenzoic acid (IBX) and bis(trifluoro-acetoxy)iodobenzene (BTI) are shown to be general reagents for regio-controlled oxidation of polycyclic aromatic phenols (PAPs) to specific isomers (ortho, para, or remote) of polycyclic aromatic quinones (PAQs). The oxidations of a series of PAPs with IBX take place under mild conditions to furnish the corresponding ortho-PAQs. In contrast, oxidations of the same series of PAPs with BTI exhibit variable regiospecificity, affording para-PAQs where structurally feasible and ortho-PAQs or remote PAQ isomers in other cases. The structures of the specific PAQ isomers formed are predictable on the basis of the inherent regioselectivities of the hypervalent iodine reagents in combination with the structural requirements of the phenol precursors. IBX and BTI are recommended as the preferred reagents for regio-controlled oxidation of PAPs to PAQs.
SYNTHESIS OF NON-K-REGION ORTHO-QUINONES OF POLYCYCLIC AROMATIC HYDROCARBONS FROM CYCLIC KETONES
Platt, Karl L.,Oesch, Franz
, p. 163 - 166 (2007/10/02)
Non-K-region o-quinones of polycyclic aromatic hydrocarbons are prepared in four steps from cyclic ketones via dehydrogenation of tetrahydrodiols with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone.
