Comprehensive in Vitro Characterization of the LSD1 Small Molecule Inhibitor Class in Oncology

Lysine-specific demethylase 1 (LSD1 or KDM1A) is a chromatin modifying enzyme playing a key role in the cell cycle and cell differentiation and proliferation through the demethylation of histones and nonhistone substrates. In addition to its enzymatic activity, LSD1 plays a fundamental scaffolding role as part of transcription silencing complexes such as rest co-repressor (CoREST) and nucleosome remodeling and deacetylase (NuRD). A host of classical amine oxidase inhibitors such as tranylcypromine, pargyline, and phenelzine together with LSD1 tool compounds such as SP-2509 and GSK-LSD1 have been extensively utilized in LSD1 mechanistic cancer studies. Additionally, several optimized new chemical entities have reached clinical trials in oncology such as ORY-1001 (iadademstat), GSK2879552, SP-2577 (seclidemstat), IMG-7289 (bomedemstat), INCB059872, and CC-90011 (pulrodemstat). Despite this, no single study exists that characterizes them all under the same experimental conditions, preventing a clear interpretation of published results. Herein, we characterize the whole LSD1 small molecule compound class as inhibitors of LSD1 catalytic activity, disruptors of SNAIL/GFI1 (SNAG)-scaffolding protein-protein interactions, inducers of cell differentiation, and potential anticancer treatments for hematological and solid tumors to yield an updated, unified perspective of this field. Our results highlight significant differences in potency and selectivity among the clinical compounds with iadademstat being the most potent and reveal that most of the tool compounds have very low activity and selectivity, suggesting some conclusions derived from their use should be taken with caution.

Discovery of a picomolar potency pharmacological corrector of the mutant CFTR chloride channel

F508del, the most frequent mutation causing cystic fibrosis (CF), results in mistrafficking and premature degradation of the CFTR chloride channel. Small molecules named correctors may rescue F508del-CFTR and therefore represent promising drugs to target the basic defect in CF. We screened a carefully designed chemical library to find F508del-CFTR correctors. The initial active compound resulting from the primary screening underwent extensive chemical optimization. The final compound, ARN23765, showed an extremely high potency in bronchial epithelial cells from F508del homozygous patients, with an EC₅₀ of 38 picomolar, which is more than 5000-fold lower compared to presently available corrector drugs. ARN23765 also showed high efficacy, synergy with other types of correctors, and compatibility with chronic VX-770 potentiator. Besides being a promising drug, particularly suited for drug combinations, ARN23765 represents a high-affinity probe for CFTR structure-function studies.

Gold(i)-catalysed cascade reactions in the synthesis of 2,3-fused indole derivatives

Unactivated alkenes and 1,3-unsubstituted indoles in gold(i)-catalysed hydroaminative/arylative cascade cyclizations.

Polysulfonylamine, CLXXXVIII [1]. Kristallstrukturen von drei Dimethylammonium-di(4-halogenbenzolsulfonyl)amiden (Halogen = Cl, Br, I) und von Dimethylammonium-di(4-methylbenzolsulfonyl)amid: Eine isotype Reihe mit strukturbestimmenden starken Wasserstoffbrücken und beiläufigen Halogenbrücken/ Polysulfonylamines, CLXXXVIII. Crystal Structures of Three Dimethylammonium Di(4-halobenzenesulfonyl)amides (Halogen = Cl, Br, I) and of Dimethylammonium Di(4-methylbenzenesulfonyl)amide: An Isotypical Series Featuring Strong Structure-determining Hydrogen Bonds and Incidental Halogen Bonds

The four title compounds, Me2NH2 +·(4-Cl/Br/I/Me-C6H4-SO2)2N-, were obtained by metathesis of dimethylammonium chloride with the corresponding silver di(arenesulfonyl)amides. The products crystallize isotypically in the monoclinic space group Cc (Z = 4, Z´ = 1). In each structure, the ionic entities associate into hydrogen-bonded chains, which propagate along the c axis of the crystals and consist of alternating cations and anions held together by charge-assisted N+-H· · ·N− and N+- H(· · ·O)2 hydrogen bonds. In the three structures containing 4-halobenzenesulfonyl groups, each hydrogen-bonded chain is linked to four neighboring chains by pairs of C-Cl/Br/I· · ·O halogen bonds, which at first sight seem to be the causative factor in the formation of catemeric head-to-tail arrays of anions propagating along the ab face diagonals. On suppressing these halogen bonds by means of halogen-methyl exchange, all essential features of the packing architecture, including the anion headto- tail arrays, are precisely maintained. It may be thus inferred that the halogen bonds occurring in the first three compounds are supportive incidentals, but do not play any structure-determining role.

Polysulfonylamine, CLXXXIX [1]. Weitere Beispiele für die O-Protonierung von Harnstoffen mit Di(organosulfonyl)aminen: Bildung und Kristallstrukturen von 1,1-Dimethyluroniumdi( 4-fluorbenzolsulfonyl)amid und Di(1-methylharnstoff)- hydrogen(I)-di(4-fluorbenzolsulfonyl)amid/ Polysulfonylamines, CLXXXIX. Additional Examples of the O-Protonation of Ureas by Di(organosulfonyl)amines: Formation and Crystal Structures of 1,1-Dimethyluronium Di(4-fluorobenzenesulfonyl)amide and Di(1-methylurea)hydrogen(I)Di(4-fluorobenzenesulfonyl) amide

Co-crystallization of N-methyl-substituted ureas with di(organosulfonyl)amines, (RSO2)2NH, leads unpredictably to either molecular co-crystals or, via proton transfer, to uronium salts. As a sequel to former reports, this communication describes the formation and the crystal structures of the new ionic compounds 1,1-dimethyluronium di(4-fluorobenzenesulfonyl)amide (1, monoclinic, space group P21/c, Z´ = 1) and di(1-methylurea)hydrogen(I) di(4-fluorobenzenesulfonyl)amide (2, triclinic, P1̄, Z´ = 1); both salts were obtained from dichloromethane/petroleum ether. In the structure of 2, the urea moieties of the cationic homoconjugate are connected by a very short [O-H· · ·O]+ hydrogen bond [d(O· · ·O) = 244.6(2) pm, θ (O-H· · ·O)≈170°, bridging H atom asymmetrically disordered over two positions]. The O-protonation induces a specific elongation of the C-O bond lengths to 131.2(2) pm in 1 or 129.5(2) and 127.4(2) pm in 2, as compared to literature data of ca. 126 pm for the unprotonated ureas. Both crystal structures are dominated by conventional two- and threecentre hydrogen bonds, which involve the OH and all NH donors and give rise to one-dimensional cation-anion arrays. In particular, the ionic entities of 1 are alternatingly associated into simple chains propagated by glide-plane operations parallel to the c axis, whereas the donor-richer structure of 2 displays inversion symmetric dimers of formula units, which are further hydrogen-bonded into strands propagated by translation parallel to the a axis.