Solid-Phase Synthesis of 2-Alkenamides from Polystyrene-Supported α-Selenocarboxylic Acids

Structure-based optimization identified novel furyl-containing 2,4-diarylaminopyrimidine analogues as ALK/ROS1 dual inhibitors with anti-mutation effects

Aiming to develop ALK/ROS1 dual inhibitors overcoming ceritinib-resistant G1202R mutant, a dedicated structure-guided modification campaign was conducted based on ALK co-crystal structures. Twenty eight diarylaminopyrimidine (DAAP) analogues possessing furan or tetrahydrofuran group were designed and synthesized, among which compound 16 bearing (dimethylamino)methyl)furan-2-yl)methyl)thio fragment was identified. Compound 16 exhibited significant cytotoxicity on ALK-positive Karpas299 and H2228 cells with IC₅₀ values of 20 nM and 110 nM. Meanwhile, compound 16 turned out as the most potent entity superior to ceritinib with IC₅₀ values of 2.8, 2.6, 3.8 and 2.3 nM against ALK^WT, ALK^L1196M, ALK^G1202R and ROS1^WT, respectively. Subsequently, western blot assay showed that compound 16 significantly suppressed ALK and its downstream protein expression in a dose-dependent manner. Alternatively, the Hoechst 33258 and AO/EB staining assays illustrated that compound 16 could induce H2228 cell apoptosis. Ultimately, the binding models of compound 16 with ALK^WT, ALK^G1202R as well as ROS1 clearly presented the essential interactions within the active site. Together, compound 16 was validated as a promising ALK/ROS1 dual inhibitor for ALK^G1202R mutation correlated tumors.

Traceless Solid-Phase Organic Synthesis

Traceless solid-phase synthesis represents an ultimate sophisticated synthetic strategy on insoluble supports. Compounds synthesized on solid supports can be released without a trace of the linker that was used to tether the intermediates during the synthesis. Thus, the target products are composed only of the components (atoms, functional groups) inherent to the target core structure. A wide variety of synthetic strategies have been developed to prepare products in a traceless manner, and this review is dedicated to all aspects of traceless solid-phase organic synthesis. Importantly, the synthesis does not need to be carried out on a linker designed for traceless synthesis; most of the synthetic approaches described herein were developed using standard, commercially available linkers (originally devised for solid-phase peptide synthesis). The type of structure prepared in a traceless fashion is not restricted. The individual synthetic approaches are divided into eight sections, each devoted to a different methodology for traceless synthesis. Each section consists of a brief outline of the synthetic strategy followed by a description of individual reported syntheses.