Heteroelement Analogues of Benzoxaborole and Related Ring Expanded Systems

Abstract

The review covers the chemistry of organoboron heterocycles structurally related to benzoxaboroles where one of the carbon atoms in a boracycle or a fused benzene ring is replaced by a heteroelement such as boron, silicon, tin, nitrogen, phosphorus, or iodine. Related ring expanded systems including those based on naphthalene and biphenyl cores are also described. The information on synthetic methodology as well as the basic structural and physicochemical characteristics of these emerging heterocycles is complemented by a presentation of their potential applications in organic synthesis and medicinal chemistry, the latter aspect being mostly focused on the promising antimicrobial activity of selected compounds.

Oxazoline scaffold in synthesis of benzosiloxaboroles and related ring-expanded heterocycles: diverse reactivity, structural peculiarities and antimicrobial activity

“…Yield 390 mg (78%). 1 8-Fluoro-9-(hydroxydimethylsilyl)-3,3-dimethyl-2,3,5-trihydro-10l4-benzo [3,4] 3,2]oxazaborol-10-ol (4c). Compound 4b (333 mg, 1.0 mmol) was treated with the solution of NaHCO 3 (125 mg, 1.5 mmol) in water (3 mL).…”

“…153-156 C. Yield 223 mg (75%). 1 (5-Fluoro-2-(7-uoro-3,3,8,8-tetramethyl-2,3-dihydro-4H,8H-1,9,11-trioxa-3a-aza-8-sila-10,11al 4 -diborabenzo[ij]cyclopenta [c]azulen-10-yl)phenyl)methanol (4d). A mixture of 4c (75 mg, 0.25 mmol) and Tavaborole (38 mg, 0.25 mmol) in acetone (2 mL) was heated at 50 C for ca.…”

“…[1][2][3] Recently, various heterocyclic organoboron compounds have attracted strong interest due to their promising properties associated with improved stability and Lewis acidity compared to analogous acyclic organoboranes. 4 Thus, they are predestined for applications in medicine as they are hydrolytically stable and resistant to oxidation in air. Benzosiloxaboroles can be regarded as silicon bioisosteres of benzoxaboroles and show analogous physicochemical and biological properties.…”

Incorporation of a Boron–Nitrogen Covalent Bond Improves the Charge-Transport and Charge-Transfer Characteristics of Organoboron Small-Molecule Acceptors for Organic Solar Cells

“…Organoboron provides a new idea to design optoelectronic materials [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. However, the development of n-type organoboron small-molecular acceptors (OSMAs) with advantages of facile synthesis, synthetic versatility, and simplified purification lags far behind that of their polymer counterparts [ 23 , 24 ].…”

Exploring the effect of substitution patterns on the symmetry of hydrogen-bonded supramolecular motifs in functionalized benzosiloxaboroles

“…17,34 Our group has been focused on the synthesis and physicochemical characterization of heteroelement analogues of benzoxaboroles, paying special attention to benzosiloxaborolesa new class of benzo-fused heterocycles characterized by improved Lewis acidity, high stability and promising antimicrobial activity. 35,36 They can be considered as silicon bioisosteres of benzoxaboroles, where the methylene group is replaced by the bulkier SiMe 2 group (Scheme 1). Benzosiloxaboroles were identified as potent antifungal and antibacterial agents, especially against Grampositive strains including S. aureus, S. epidermidis and E. faecalis.…”