Discovery of Benzoylsulfonohydrazides as Potent Inhibitors of the Histone Acetyltransferase KAT6A.

A high-throughput screen for inhibitors of the histone acetyltransferase, KAT6A, led to identification of an aryl sulfonohydrazide derivative (CTX-0124143) that inhibited KAT6A with an IC of 1.0 μM. Elaboration of the structure-activity relationship and medicinal chemistry optimization led to the discovery of WM-8014 (), a highly potent inhibitor of KAT6A (IC = 0.

Carbonic Anhydrase XII Inhibitors Overcome Temozolomide Resistance in Glioblastoma.

The natural product primary sulfonamide, psammaplin C (1), when used in combination with clinically used chemotherapeutic drugs, including temozolomide, reverses multidrug resistance and increases survival in glioblastoma, a highly aggressive primary brain tumor. We showed previously that the mechanism of action of 1 is novel, acting to indirectly interfere with P-glycoprotein drug efflux activity as a consequence of carbonic anhydrase XII (CA XII) inhibition. To build structure-activity relationships, 45 derivatives of 1 were designed, synthesized, and evaluated against a panel of CA isoforms.

Carbonic Anhydrase XII Inhibitors Overcome P-Glycoprotein-Mediated Resistance to Temozolomide in Glioblastoma.

The role of carbonic anhydrase XII (CAXII) in the chemoresistance of glioblastoma is unexplored. We found CAXII and P-glycoprotein (Pgp) coexpressed in neurospheres derived from 3 of 3 patients with different genetic backgrounds and low response to temozolomide (time to recurrence: 6-9 months). CAXII was necessary for the Pgp efflux of temozolomide and second-line chemotherapeutic drugs, determining chemoresistance in neurospheres.

Synthesis, structure and bioactivity of primary sulfamate-containing natural products.

Here we report the synthesis of natural products (NPs) 5'-O-sulfamoyl adenosine 1 and 5'-O-sulfamoyl-2-chloroadenosine 2. As primary sulfamates these compounds represent an uncommon class of NPs, furthermore there are few NPs known that contain a NS bond. Compounds 1 and 2 were evaluated for inhibition of carbonic anhydrases (CA), a metalloenzyme family where the primary sulfamate is known to coordinate to the active site zinc and form key hydrogen bonds with adjacent CA active site residues.

Identification of a New Zinc Binding Chemotype by Fragment Screening.

The discovery of a new zinc binding chemotype from screening a nonbiased fragment library is reported. Using the orthogonal fragment screening methods of native state mass spectrometry and surface plasmon resonance a 3-unsubstituted 2,4-oxazolidinedione fragment was found to have low micromolar binding affinity to the zinc metalloenzyme carbonic anhydrase II (CA II). This affinity approached that of fragment sized primary benzenesulfonamides, the classical zinc binding group found in most CA II inhibitors.

An Unusual Natural Product Primary Sulfonamide: Synthesis, Carbonic Anhydrase Inhibition, and Protein X-ray Structures of Psammaplin C.

Psammaplin C is one of only two described natural product primary sulfonamides. Here we report the synthesis of psammaplin C and evaluate the inhibition profile against therapeutically relevant carbonic anhydrase (CA) zinc metalloenzymes. The compound exhibited unprecedented inhibition of an important cancer-associated isozyme, hCA XII, with a Ki of 0.

Isoform-selective inhibitory profile of 2-imidazoline-substituted benzene sulfonamides against a panel of human carbonic anhydrases.

A series of novel benzene sulfonamides (previously evaluated as selective cyclooxygenase-2 inhibitors) has been profiled against human carbonic anhydrases I, II, IV and VII in an attempt to observe the manifestation of the well established "tail" approach for designing potent, isoform-selective inhibitors of carbonic anhydrases (CAs, EC 4.2.1.

Library of diversely substituted 2-(quinolin-4-yl)imidazolines delivers novel non-cytotoxic antitubercular leads.

A novel library based on quinolin-4-ylimidazoline core was designed to incorporate a general quinoline antimicrobial pharmacophore. A synthesis of the well-characterized library of 36 compounds was achieved using the Pd-catalyzed Buchwald-Hartwig-type imidazoline arylation chemistry developed earlier. Compounds were tested for biological activity and were found to possess no antimalarial activity.

Natural Product Primary Sulfonamides and Primary Sulfamates.

Primary sulfonamide and primary sulfamate functional groups feature prominently in the structures of U.S. FDA-approved drugs.

Panel docking of small-molecule libraries - Prospects to improve efficiency of lead compound discovery.

Computational docking as a means to prioritise small molecules in drug discovery projects remains a highly popular in silico screening approach. Contemporary docking approaches without experimental parametrisation can reliably differentiate active and inactive chemotypes in a protein binding site, but the absence of a correlation between the score of a predicted binding pose and the biological activity of the molecule presents a clear limitation. Several novel or improved computational approaches have been developed in the recent past to aid in screening and profiling of small-molecule ligands for drug discovery, but also more broadly in developing conceptual relationships between different protein targets by chemical probing.

Potent, orally available, selective COX-2 inhibitors based on 2-imidazoline core.

A novel series of compounds containing a polar, non-flat 2-imidazoline core was designed based on the SAR information available for aromatic azole cyclooxygenase-2 inhibitors. While the majority of the compounds prepared using an earlier developed imidazoline N-arylation methodology turned out to be inferior to the known COX-2 inhibitors, one lead compound displayed potency (300 nM) comparable to clinically used Celecoxib and was shown to be more selective. The series represents the first example of selective COX-2 inhibitors built around a distinctly polar core, contradicting an earlier accepted view that a lipophilic scaffold is required for high inhibitor potency.