Organic Process Research & Development最新文献

A route to the key α-bromoketone intermediate for the synthesis of an imidazo[1,2-b]pyridazine IL-17A inhibitor via Horner–Wadsworth–Emmons condensation of commercially available 4,4-difluorocyclohexan-1-one (8) and methyl 2-(((benzyloxy)carbonyl)amino)-2-(dimethoxyphosphoryl)acetate (7) was developed and scaled up to support the production of drug substance for toxicology and clinical studies. The α,β-didehydroamino acid ester product 13 from Horner–Wadsworth–Emmons condensation was hydrolyzed under basic conditions to afford the corresponding N-protected α,β-didehydroamino acid 14, which was asymmetrically hydrogenated in the presence of the Ru-S-Xyl-Segphos dimer to afford the desired chiral amino acid 15. After activation with carbonyl diimidazole, the resulting acyl imidazole was reacted with the magnesium ethyl malonate complex to afford a β-oxo ester 17, which was brominated followed by concomitant decarboxylation after enzymatic ester hydrolysis with Lipozyme TL IM to afford the desired α-bromoketone intermediate 5. Stress tests and range-finding studies were carried out for all steps to support production. The optimized process was successfully scaled up to deliver 110 kg of α-bromoketone intermediate 5 to support the production of an IL-17A inhibitor. The overall yield of the optimized process was significantly improved to 46.5% from the 19.1% of the preclinical supplies process.

Integrating the diazotization and coupling reactions in solid–liquid heterogeneous systems to achieve large-scale, multistep continuous flow synthesis of water-soluble azo dyes remains a significant challenge. During the diazotization process of water-soluble azo dyes, considerable diazonium salt may precipitate, posing potential safety risks. In this study, we established a continuous dynamic tubular reaction system to achieve the multistep continuous heterogeneous synthesis of C.I. Reactive Red 195, a representative water-soluble azo dye. The optimal conditions for continuous diazotization and coupling reactions were determined, achieving a high throughput of 120 L/h and a yield of up to 736 kg/day. The purity of the synthesized dye increased by 20% compared to the commercial C.I. Reactive Red 195, with the K/S value rising from 19.07 to 22.16, indicating enhanced dyeing performance. Density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations show that 2-naphthylamine-1,5-disulfonic acid diazonium salt (NADA-DS) spontaneously aggregates into stable clusters due to dispersion forces, which leads to precipitation. Furthermore, the thermal stability, impact sensitivity, explosive propagation, and decomposition activation energy of NADA-DS were investigated. The severity and possibility of thermal runaway during the continuous diazotization process are classified as level 1. The risk matrix indicates that the continuous diazotization process risk is acceptable, with the Stoessel criticality diagram categorizing the hazard level as grade 1, signifying a low level of risk. This study promotes safer, more efficient, and sustainable production of water-soluble azo dyes.

JNJ-7950 is a potent small-molecule respiratory syncytial virus (RSV) inhibitor with a long-acting profile in preclinical species. The design and development of a convergent synthetic route accelerated the discovery and development of JNJ-7950. First, the new synthetic route supported the lead candidate (JNJ-7950) selection process and later was adapted to provide a large-scale clinical batch. A shorter and cost-effective synthetic route to the key spiro-azetidine moiety exploited an intramolecular copper-catalyzed C–N coupling. The development of an efficient and sustainable process for telescoping three steps in a single solvent provided the benzimidazole moiety with an 85% overall yield. The spiro-azetidine and the benzimidazole moieties were coupled to provide JNJ-7950 in 48% overall yield with excellent purity over the six longest linear steps. Two GMP batches (6 and 12 kg) of JNJ-7950 were manufactured in parenteral grade quality to support long-acting injectable formulation development and early clinical need.

The Baeyer–Villiger reaction is an established oxidative process that is applied for structural and functional group modification. We have applied the Baeyer–Villiger process to prepare 4′-oxo nucleosides. The application of Baeyer–Villiger oxidation to prepare MeMOP, a complex amidite used in the reported GalXC platform, will be discussed. A large-scale process to prepare MeMOP with an improved economic and operational safety risk profile will be highlighted. This novel application of the Baeyer–Villiger reaction to nucleoside platforms was used to scale up the MeMOP phosphoramidite process, which supported multiple clinical trials enabling siRNA campaigns.