Methamphetamine (METH) substance use disorder is a long-standing and ever-growing public health concern. Efforts to develop successful immunotherapies are ongoing with vaccines that generate strong antibody responses are an area of significant research interest. Herein, we describe the development of a METH Hapten conjugate vaccine comprised of either two short-length peptides as linkers and mannan as an immunogenic delivery carrier. Initially, Hapten 1 (with a monoamine linker) and Hapten 2 (with a diamine linker) were synthesised. Each step of the Hapten synthesis were characterized by LC-MS and purified by Flash Chromatography and the identity of the purified Haptens were confirmed by 1H NMR. Haptens were conjugated with mannan (a polymannose), and conjugation efficiency was confirmed by LC-MS, TLC, 1H NMR, and 2,4 DNPH tests. The immunogenic potential of the two conjugated vaccines were assessed in mice with a 3-dose regimen. Concentrations of anti-METH antibodies were measured by enzyme-linked immunosorbent assay. All the analytical techniques confirmed the identity of Hapten 1 and 2 during the synthetic phase. Similarly, all the analytical approaches confirmed the conjugation between the Haptens and mannan. Mouse immunogenicity studies confirmed that both vaccine candidates were immunogenic and the vaccine with the monoamine linker plus adjuvants induced the highest antibody response after the second booster.
Since transition-metal-catalyzed reactions are one of the most powerful and direct approaches for the synthesis of organic molecules, translating them to biological systems for biomedical applications is an emerging field. The manipulation of transition metal reactions in biological settings for uncaging prodrugs and synthesizing bioactive drugs has been widely studied. To expand the toolbox of transition-metal-mediated prodrug strategy, this work introduces the 2′-alkynl-biphenylamine precursors for the synthesis of phenanthridine derivatives using a water-compatible gold-catalyzed hydroamination under mild conditions. Moreover, the structure–reactivity relationship revealed that the nucleophilicity of the amine group in the precursor was critical for facilitating the gold-catalyzed synthesis of phenanthridine derivatives. The research shows the potential to be used for phenanthridine-based prodrug designs in an aqueous solution.
Amyloid beta peptide (Aβ) and hyperphosphorylated neuronal tau proteins accumulate in neurofibrillary tangles in Alzheimer’s disease (AD), a chronic neurodegenerative illness. Chronic inflammation in the brain, which promotes disease progression, is another feature of the Alzheimer’s disease pathogenesis. Approximately 60–70 % of dementia cases are caused by AD. The development of effective therapies for the treatment of AD is urgently needed given the severity of the condition and its rapidly rising prevalence. Cholinesterase inhibitors, beta-amyloid (A-beta), tau inhibitors, and many other medications are currently used as preventive medicine for AD. These medications can temporarily suppress dementia symptoms but cannot halt or reverse the disease’s progression. Many international pharmaceutical companies have tried numerous times to develop an amyloid clearing medication based on the amyloid hypothesis, but without success. Therefore, the amyloid theory may not be entirely plausible. This review mainly covers the recent and important reported pharmacophores as the starting point to discuss already known targets like tau, butyrylcholinesterase, amyloid beta, and acetylcholinesterase and covers the literature between years 2019–2024.