Herein, we report the first enantioselective annulation of α‐arylidene pyrazolones through a formal C(sp3)−H activation under mild conditions enabled by highly variable RhIII‐Cpx catalysts. The method has a wide substrate scope and proceeds with good to excellent yields and enantioselectivities. Its synthetic utility was demonstrated by the late‐stage functionalization of drugs and natural products as well as the preparation of enantioenriched [3]dendralenes. Preliminary biological investigations also identified the spiropyrazolones as a novel class of Hedgehog pathway inhibitors.

Axially chiral 4-arylisoquinolones are endowed with pronounced bioactivity, and methods for their efficient synthesis have gained widespread attention. However, enantioselective synthesis of axially chiral 4-arylisoquinolones by means of C-H activation has not been reported to date. Described here is a rhodium (III)-catalyzed C-H bond activation and annulation for the atroposelective synthesis of axially chiral 4-arylisoquinolones. The method employs chiral cyclopentadienyl ligands embodying a piperidine ring as backbone and yields the atropisomers with good to excellent yields and enantioselectivity. Biological relevance of the 4-arylisoquinolones was demonstrated by their investigation in different cellular assays, leading to the discovery of novel non-SMO (SMO= smoothened) binding Hedgehog pathway inhibitors.

RhIII‐catalyzed C−H functionalization reaction yielding isoindolinones from aryl hydroxamates and ortho‐substituted styrenes is reported. The reaction proceeds smoothly under mild conditions at room temperature, and tolerates a range of functional groups. Experimental and computational investigations support that the high regioselectivity observed for these substrates results from the presence of an ortho‐substituent embedded in the styrene. The resulting isoindolinones are valuable building blocks for the synthesis of bioactive compounds. They provide easy access to the natural‐product‐like compounds, isoindolobenzazepines, in a one‐pot two‐step reaction. Selected isoindolinones inhibited Hedgehog (Hh)‐dependent differentiation of multipotent murine mesenchymal progenitor stem cells into osteoblasts.

We describe the synthesis and biological evaluation of a new natural product‐inspired compound class obtained by combining the conceptually complementary pseudo‐natural product (pseudo‐NP) design strategy and a formal adaptation of the complexity‐to‐diversity ring distortion approach. Fragment‐sized α‐methylene‐sesquiterpene lactones, whose scaffolds can formally be viewed as related to each other or are obtained by ring distortion, were combined with alkaloid‐derived pyrrolidine fragments by means of highly selective stereocomplementary 1,3‐dipolar cycloaddition reactions. The resulting pseudo‐sesquiterpenoid alkaloids were found to be both chemically and biologically diverse, and their biological performance distinctly depends on both the structure of the sesquiterpene lactone‐derived scaffolds and the stereochemistry of the pyrrolidine fragment. Biological investigation of the compound collection led to the discovery of a novel chemotype inhibiting Hedgehog‐dependent osteoblast differentiation

Axially chiral 4-arylisoquinolones are endowed with pronounced bioactivity,a nd methods for their efficient synthesis have gained widespread attention. However,e nantioselective synthesis of axially chiral 4-arylisoquinolones by means of C À Ha ctivation has not been reported to date.D escribed here is ar hodium (III)-catalyzed C À Hb ond activation and annulation for the atroposelective synthesis of axially chiral 4arylisoquinolones.T he method employs chiral cyclopentadienyl ligands embodying ap iperidine ring as backbone and yields the atropisomers with good to excellent yields and enantioselectivity.B iological relevance of the 4-arylisoquinolones was demonstrated by their investigation in different cellular assays,l eading to the discovery of novel non-SMO (SMO = smoothened) binding Hedgehog pathwayi nhibitors.

The Hedgehog (Hh) signaling pathway is crucial for vertebrate embryonic development, tissue homeostasis and regeneration. Hh signaling is upregulated in basal cell carcinoma and medulloblastoma and Hh pathway inhibitors targeting the Smoothened (SMO) protein are in clinical use. However, the signaling cascade is incompletely understood and novel druggable proteins in the pathway are in high demand. We describe the discovery of the Hh‐pathway modulator Pipinib by means of cell‐based screening. Target identification and validation revealed that Pipinib selectively inhibits phosphatidylinositol 4‐kinase IIIβ (PI4KB) and suppresses GLI‐mediated transcription and Hh target gene expression by impairing SMO translocation to the cilium. Therefore, inhibition of PI4KB and, consequently, reduction in phosphatidyl‐4‐phosphate levels may be considered an alternative approach to inhibit SMO function and thus, Hedgehog signaling.

Pseudo‐natural products (pseudo‐NPs) are de novo combinations of natural product (NP) fragments that define novel bioactive chemotypes. For their discovery, new design principles are being sought. Previously, pseudo‐NPs were synthesized by the combination of fragments originating from biosynthetically unrelated NPs to guarantee structural novelty and novel bioactivity. We report the combination of fragments from biosynthetically related NPs in novel arrangements to yield a novel chemotype with activity not shared by the guiding fragments. We describe the synthesis of the polyketide pseudo‐NP grismonone and identify it as a structurally novel and potent inhibitor of Hedgehog signaling. The insight that the de novo combination of fragments derived from biosynthetically related NPs may also yield new biologically relevant compound classes with unexpected bioactivity may be considered a chemical extension or diversion of existing biosynthetic pathways and greatly expands the opportunities for exploration of biologically relevant chemical space by means of the pseudo‐NP principle.

Reported is the identification of the furo [3,2b]pyridine core as an ovel scaffold for potent and highly selective inhibitors of cdc-like kinases (CLKs) and efficient modulators of the Hedgehog signaling pathway.I nitially, ad iverse target compound set was prepared by synthetic sequences based on chemoselective metal-mediated couplings, including assembly of the furo[3,2-b]pyridine scaffold by copper-mediated oxidative cyclization. Optimization of the subseries containing 3,5-disubstituted furo[3,2-b]pyridines afforded potent, cell-active,a nd highly selective inhibitors of CLKs.P rofiling of the kinase-inactive subset of 3,5,7-trisubstituted furo[3,2-b]pyridines revealed sub-micromolar modulators of the Hedgehog pathway.