Fluorous synthesis of sclerotigenin-type benzodiazepine-quinazolinones

Pharmaceutical prospects of naturally occurring quinazolinone and its derivatives

Quinazolinones belong to a family of heterocyclic nitrogen compounds that have attracted increasing interest because of their broad spectrum of biological functions. This review describes three types of natural quinazolinones and their synthesized derivatives and summarizes their various pharmacological activities, including antifungal, anti-tumor, anti-malaria, anticonvulsant, anti-microbial, anti-inflammatory and antihyperlipidemic activities. In addition, structure-activity relationships of quinazolinone derivatives are also reviewed.

1,5-Benzodiazepine derivatives as potential antimicrobial agents: design, synthesis, biological evaluation, and structure–activity relationships

36 novel 1,5-benzodiazepine derivatives were synthesized and evaluated for their in vitro antimicrobial activity. The results revealed that most of the 1,5-benzodiazepine derivatives exhibited considerable potency against all of the tested strains.

Visual monitoring of solid-phase extraction using chromogenic fluorous synthesis supports

Reductive aminations and further transformations of an azo dye and fluorous tagged aldehyde are described. The intensely colored 2,4-dialkoxybenzyl protected amines undergo Fmoc-based peptide coupling, Suzuki reactions, and sulfonamide formation with product isolation facilitated by visual monitoring of fluorous solid phase extraction. Target compounds are released from the supports in high yields and purities by treatment with trifluoroacetic acid (TFA).

Microwave-assisted fluorous synthesis of a 1,4-benzodiazepine-2,5-dione library

Fluorous displaceable linker-facilitated synthesis of 1,4-benzodiazepine-2,5-dione library has been developed. Perfluorooctanesulfonyl protected 4-hydroxy benzaldehydes were used as the limiting agent for Ugi four-component reactions to form condensed products. Postcondensation reactions of the Ugi products generated 1,4-benzodiazepine-2,5-dione ring skeleton. Microwave-assisted Suzuki coupling reactions removed the fluorous tag and introduced biaryl functionality to the benzodiazepine ring. The library scaffold has four points of substitution diversities. The fluorous tag facilitated the intermediate purifications using fluorous solid-phase extraction (F-SPE) and had no negative impact on the reactivity of the Ugi reactions and postcondensation reactions.

Fluorous-enhanced multicomponent reactions for making drug-like library scaffolds

Multicomponent reactions (MCRs) generate multiple bonds in a single reaction process, which is highly efficient to construct relatively complex molecules. Conducting post-MCR modification reactions further increases the molecular complexity and diversity. MCR has become a powerful approach to make drug-like molecules in lead generation chemistry. In fluorous MCR (F-MCR), one of the starting materials is attached to a fluorous tag and used as the limiting agent. After the MCR, the fluorous component is fished out from the reaction mixture and used for post-MCR modifications. The fluorous tag can be finally removed in traceless fashion by displacement or cyclization reactions. Unique fluorous technology such as fluorous solid-phase extraction (F-SPE) facilitates the separation process. Other techniques such as microwave irradiation and plate-to-plate SPE can also be used to make the F-MCR even more efficient. Syntheses of unique heterocyclic and natural product-like library scaffolds using Ugi/de-Boc/cyclization, MCR/Suzuki coupling, and [3+2] cycloaddition/de-tag/cyclization protocols are described in this paper.