Publications by authors named "Lawrence Hamann"

CaMKK2 signals through AMPK-dependent and AMPK-independent pathways to trigger cellular outputs including proliferation, differentiation, and migration, resulting in changes to metabolism, bone mass accrual, neuronal function, hematopoiesis, and immunity. CAMKK2 is upregulated in tumors including hepatocellular carcinoma, prostate, breast, and gastric cancer, and genetic deletion in myeloid cells results in increased antitumor immunity in several syngeneic models. Validation of the biological roles of CaMKK2 has relied on genetic deletion or small molecule inhibitors with activity against several biological targets.

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The allosteric inhibitor of the mechanistic target of rapamycin (mTOR) everolimus reduces seizures in tuberous sclerosis complex (TSC) patients through partial inhibition of mTOR functions. Due to its limited brain permeability, we sought to develop a catalytic mTOR inhibitor optimized for central nervous system (CNS) indications. We recently reported an mTOR inhibitor () that is able to block mTOR functions in the mouse brain and extend the survival of mice with neuronal-specific ablation of the 1 gene.

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Myeloperoxidase (MPO) is a heme-containing peroxidase from phagocytic cells, which plays an important role in the innate immune response. The primary anti-microbial function of MPO is achieved by catalyzing the oxidation of halides by hydrogen peroxide (HO). Upon activation of phagocytes, MPO activity is detectable in both phagosomes and extracellularly, where it can remain or transcytose into interstitial compartments.

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Retinoic acid receptor-related orphan nuclear receptor (ROR) γt is a member of the RORC nuclear hormone receptor family of transcription factors. RORγt functions as a critical regulator of thymopoiesis and immune responses. RORγt is expressed in multiple immune cell populations including Th17 cells, where its primary function is regulation of immune responses to bacteria and fungi through IL-17A production.

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The second biannual Alpine Winter Conference on Medicinal and Synthetic Chemistry (short: Alpine Winter Conference) took place January 19-23, 2020, in St. Anton in western Austria. There were roughly 180 attendees from around the globe, making this mid-sized conference particularly conducive to networking and exchanging ideas over the course of four and a half days.

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Spinal muscular atrophy (SMA) is a debilitating neuromuscular disease caused by low levels of functional survival motor neuron protein (SMN) resulting from a deletion or loss of function mutation of the survival motor neuron 1 () gene. Branaplam () elevates levels of full-length SMN protein in vivo by modulating the splicing of the related gene to enhance the exon-7 inclusion and increase levels of the SMN. The intramolecular hydrogen bond present in the 2-hydroxyphenyl pyridazine core of enforces a planar conformation of the biaryl system and is critical for the compound activity.

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This paper describes an intermolecular cross-selective [2 + 2] photocycloaddition reaction of exocyclic arylidene oxetanes, azetidines, and cyclobutanes with simple electron-deficient alkenes. The reaction takes place under mild conditions using a commercially available Ir(III) photosensitizer upon blue light irradiation. This transformation provides access to a range of polysubstituted 2-oxaspiro[3.

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Intermolecular C-C bond-forming reactions are underdeveloped transformations in the field of biocatalysis. Here we report a photoenzymatic intermolecular hydroalkylation of olefins catalyzed by flavin-dependent 'ene'-reductases. Radical initiation occurs via photoexcitation of a rare high-order enzyme-templated charge-transfer complex that forms between an alkene, α-chloroamide, and flavin hydroquinone.

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Myeloperoxidase (MPO) activity and subsequent generation of hypochlorous acid has been associated with the killing of host-invading microorganisms (e.g. bacteria, viruses, and fungi).

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Thalidomide-dependent degradation of the embryonic transcription factor SALL4 by the CRL4 E3 ubiquitin ligase is a plausible major driver of thalidomide teratogenicity. The structure of the second zinc finger of SALL4 in complex with pomalidomide, cereblon and DDB1 reveals the molecular details of recruitment. Sequence differences and a shifted binding position relative to Ikaros offer a path to the rational design of cereblon-binding drugs with reduced teratogenic risk.

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Many patients with multiple myeloma (MM) initially respond to treatment with modern combination regimens including immunomodulatory agents (lenalidomide and pomalidomide) and proteasome inhibitors. However, some patients lack an initial response to therapy (i.e.

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A large proportion of medicinally relevant molecules bear nitrogen and sp-hybridized carbon functionalities. Overwhelmingly, these atoms are found as part of (hetero)cyclic structures. Despite their importance, synthetic approaches to saturated nitrogen heterocycles are limited to several established stoichiometric alkylation techniques, as well as a few methods involving C-H bond activation.

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Recent clinical evaluation of everolimus for seizure reduction in patients with tuberous sclerosis complex (TSC), a disease with overactivated mechanistic target of rapamycin (mTOR) signaling, has demonstrated the therapeutic value of mTOR inhibitors for central nervous system (CNS) indications. Given that everolimus is an incomplete inhibitor of the mTOR function, we sought to develop a new mTOR inhibitor that has improved properties and is suitable for CNS disorders. Starting from an in-house purine-based compound, optimization of the physicochemical properties of a thiazolopyrimidine series led to the discovery of the small molecule , a potent and selective brain-penetrant ATP-competitive mTOR inhibitor.

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Article Synopsis
  • Cellular processes often rely on the regulation of protein-protein complexes, particularly through the action of E3 ubiquitin ligases that tag proteins for degradation.
  • Recent research shows that small molecules can redirect this protein destruction process, which opens new avenues for drug discovery aimed at diseases.
  • The Innovations review will specifically focus on cereblon as a case study to explore various strategies for targeted protein degradation.
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Targeted protein degradation as a therapeutic modality has seen dramatic progress and massive investment in recent years because of the convergence of two key scientific breakthroughs: optimization of first-generation peptidic proteolysis-targeted chimeras (PROTACs) into more drug-like molecules able to support in vivo proof of concept and the discovery that clinical molecules function as degraders by binding and repurposing the proteins cereblon and DCAF15. This provided clinical validation for the general approach through the cereblon modulator class of drugs and provided highly drug-like and ligand-efficient E3 ligase binders upon which to tether target-binding moieties. Increasingly rational and systematic approaches including biophysical and structural studies on ternary complexes are being leveraged as the field advances.

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Spinal muscular atrophy (SMA), a rare neuromuscular disorder, is the leading genetic cause of death in infants and toddlers. SMA is caused by the deletion or a loss of function mutation of the survival motor neuron 1 (SMN1) gene. In humans, a second closely related gene SMN2 exists; however it codes for a less stable SMN protein.

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Targeted protein degradation via small-molecule modulation of cereblon offers vast potential for the development of new therapeutics. Cereblon-binding therapeutics carry the safety risks of thalidomide, which caused an epidemic of severe birth defects characterized by forelimb shortening or phocomelia. Here we show that thalidomide is not teratogenic in transgenic mice expressing human cereblon, indicating that binding to cereblon is not sufficient to cause birth defects.

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Myeloperoxidase (MPO) is a leukocyte-derived redox enzyme that has been linked to oxidative stress and damage in many inflammatory states, including cardiovascular disease. We have discovered aminopyridines that are potent mechanism-based inhibitors of MPO, with significant selectivity over the closely related thyroid peroxidase. 1-((6-Aminopyridin-3-yl)methyl)-3-(4-bromophenyl)urea (Aminopyridine 2) inhibited MPO in human plasma and blocked MPO-dependent vasomotor dysfunction ex vivo in rat aortic rings.

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In breast cancer, estrogen receptor alpha (ERα) positive cancer accounts for approximately 74% of all diagnoses, and in these settings, it is a primary driver of cell proliferation. Treatment of ERα positive breast cancer has long relied on endocrine therapies such as selective estrogen receptor modulators, aromatase inhibitors, and selective estrogen receptor degraders (SERDs). The steroid-based anti-estrogen fulvestrant (5), the only approved SERD, is effective in patients who have not previously been treated with endocrine therapy as well as in patients who have progressed after receiving other endocrine therapies.

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Over the past several decades, the frequency of antibacterial resistance in hospitals, including multidrug resistance (MDR) and its association with serious infectious diseases, has increased at alarming rates. Pseudomonas aeruginosa is a leading cause of nosocomial infections, and resistance to virtually all approved antibacterial agents is emerging in this pathogen. To address the need for new agents to treat MDR P.

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Tetrahydroisoquinoline 40 has been identified as a potent ERα antagonist and selective estrogen receptor degrader (SERD), exhibiting good oral bioavailability, antitumor efficacy, and SERD activity in vivo. We outline the discovery and chemical optimization of the THIQ scaffold leading to THIQ 40 and showcase the racemization of the scaffold, pharmacokinetic studies in preclinical species, and the in vivo efficacy of THIQ 40 in a MCF-7 human breast cancer xenograft model.

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Can classical and modern chemical C-H oxidation reactions complement biotransformation in the synthesis of drug metabolites? We have surveyed the literature in an effort to try to answer this important question of major practical significance in the pharmaceutical industry. Drug metabolites are required throughout all phases of the drug discovery and development process; however, their synthesis is still an unsolved problem. This Review, not intended to be comprehensive or historical, highlights relevant applications of chemical C-H oxidation reactions, electrochemistry and microfluidic technologies to drug templates in order to access drug metabolites, and also highlights promising reactions to this end.

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Daclatasvir is a first-in-class, potent, and selective inhibitor of the hepatitis C virus nonstructural protein 5A replication complex. In support of nonclinical studies during discovery and exploratory development, liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance were used in connection with synthetic and radiosynthetic approaches to investigate the biotransformation of daclatasvir in vitro and in cynomolgus monkeys, dogs, mice, and rats. The results of these studies indicated that disposition of daclatasvir was accomplished mainly by the release of unchanged daclatasvir into bile and feces and, secondarily, by oxidative metabolism.

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Autophagy is a dynamic process that regulates lysosomal-dependent degradation of cellular components. Until recently the study of autophagy has been hampered by the lack of reliable pharmacological tools, but selective inhibitors are now available to modulate the PI 3-kinase VPS34, which is required for autophagy. Here we describe the discovery of potent and selective VPS34 inhibitors, their pharmacokinetic (PK) properties, and ability to inhibit autophagy in cellular and mouse models.

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