Rapid Synthesis of Aryl Fluorides in Continuous Flow through the Balz-Schiemann Reaction.

The Balz-Schiemann reaction remains a highly utilized means for preparing aryl fluorides from anilines. However, the limitations associated with handling aryl diazonium salts often hinder both the substrate scope and scalability of this reaction. To address this, a new continuous flow protocol was developed that eliminates the need to isolate the aryl diazonium salts. The new process has enabled the fluorination of an array of aryl and heteroaryl amines.

A general, enantioselective synthesis of N-alkyl terminal aziridines and C2-functionalized azetidines via organocatalysis.

A short, high-yielding protocol involving the enantioselective α-chlorination of aldehydes has been developed for the enantioselective synthesis of C2-functionalized aziridines and N-alkyl terminal azetidines from a common intermediate. This methodology allows for the rapid preparation of functionalized aziridines in 50-73% overall yields and 88-94% ee, and azetidines in 22-32% overall yields and 84-92% ee. Moreover, we developed a scalable and cost-effective route to the key organocatalyst (54% overall yield, >95% dr).

A General, Enantioselective Synthesis of 1-Azabicyclo[m.n.0]alkane Ring Systems.

In this Letter, we describe a novel approach for the general and enantioselective synthesis of a diverse array of small to large 1-azabicyclo[m.n.0]alkyl ring systems with an embedded olefin handle for further functionalization. The stereochemistry is established via a highly diastereoselective indium-mediated allylation of an Ellman sulfinimine in greater than 9:1 dr., which is readily separable by column chromatography to afford a single diastereomer. This methodology allows for the rapid preparation of 1-azabicyclo[m.n.0]alkane ring systems that are not readily accessible through any other chemistry in excellent overall yields and, for many systems, the only enantioselective preparation reported to date.

A versatile enantioselective synthesis of azabicyclic ring systems: a concise total synthesis of (+)-grandisine†D and unnatural analogues.

Closing in on azacines: We have developed a new six step approach for the rapid and enantioselective synthesis of indolizidine, pyrrolo[1,2-a]azepine, and pyrrolo[1,2-a]azocine azabicyclic systems and their respective lactam congeners, which are found in a host of natural products as well as pharmaceutical preparations. This protocol enables a concise enantioselective total synthesis of (+)-grandisine D in 16.4 % overall yield from commercial materials (see scheme).

Discovery and Optimization of Pyrazole Amides as Inhibitors of ELOVL1.

Accumulation of very long chain fatty acids (VLCFAs) due to defects in ATP binding cassette protein D1 (ABCD1) is thought to underlie the pathologies observed in adrenoleukodystrophy (ALD). Pursuing a substrate reduction approach based on the inhibition of elongation of very long chain fatty acid 1 enzyme (ELOVL1), we explored a series of thiazole amides that evolved into compound 27─a highly potent, central nervous system (CNS)-penetrant compound with favorable in vivo pharmacokinetics. Compound 27 selectively inhibits ELOVL1, reducing C26:0 VLCFA synthesis in ALD patient fibroblasts, lymphocytes, and microglia. In mouse models of ALD, compound 27 treatment reduced C26:0 VLCFA concentrations to near-wild-type levels in blood and up to 65% in the brain, a disease-relevant tissue. Preclinical safety findings in the skin, eye, and CNS precluded progression; the origin and relevance of these findings require further study. ELOVL1 inhibition is an effective approach for normalizing VLCFAs in models of ALD.

Electrochemically Enabled Chan-Lam Couplings of Aryl Boronic Acids and Anilines.

The Chan-Lam reaction remains a highly utilized transformation for C-N bond formation. However, anilines remain problematic substrates due to their lower nucleophilicity. To address this problem, we developed an electrochemically mediated Chan-Lam coupling of aryl boronic acids and amines utilizing a dual copper anode/cathode system. The mild conditions identified have enabled the preparation of a wide range of functionalized biarylanilines in good yields and chemoselectivities.

High-affinity small-molecule inhibitors of the menin-mixed lineage leukemia (MLL) interaction closely mimic a natural protein-protein interaction.

The protein-protein interaction (PPI) between menin and mixed lineage leukemia (MLL) plays a critical role in acute leukemias, and inhibition of this interaction represents a new potential therapeutic strategy for MLL leukemias. We report development of a novel class of small-molecule inhibitors of the menin-MLL interaction, the hydroxy- and aminomethylpiperidine compounds, which originated from HTS of ∼288000 small molecules. We determined menin-inhibitor co-crystal structures and found that these compounds closely mimic all key interactions of MLL with menin. Extensive crystallography studies combined with structure-based design were applied for optimization of these compounds, resulting in MIV-6R, which inhibits the menin-MLL interaction with IC50 = 56 nM. Treatment with MIV-6 demonstrated strong and selective effects in MLL leukemia cells, validating specific mechanism of action. Our studies provide novel and attractive scaffold as a new potential therapeutic approach for MLL leukemias and demonstrate an example of PPI amenable to inhibition by small molecules.

Enantioselective total synthesis of (+)-amabiline.

The first total synthesis of (+)-amabiline, an unsaturated pyrrolizidine alkaloid from Cynoglossum amabile, is reported. This convergent, enantioselective synthesis proceeds in 15 steps (10-step longest linear sequence) in 6.2% overall yield and features novel methodology to construct the unsaturated pyrrolizidine or (-)-supinidine core.