High purity diaminophenothiazinium compounds including methylthioninium chloride (MTC)
US9555043B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 19, 2016 |
| Grant date | Jan 31, 2017 |
| Priority date | — |
| Expiry date | Jan 19, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A50/30
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
This invention pertains generally to the field of chemical synthesis and purification, and more specifically to methods of synthesizing and purifying certain 3,7 diamino-phenothiazin-5-ium compounds (referred to herein as “diaminophenothiaziniumcompounds”) including Methythioninium Chloride (MTC) (also known as Methylene Blue). In one embodiment, the method comprises the steps of, in order: nitrosylation (NOS); nitrosyl reduction (NR); thiosulfonic acid formation (TSAF); oxidative coupling (OC); Cr(VI) reduction (CR); isolation and purification of zwitterionic intermediate (IAPOZI); ring closure (RC); chloride salt-formation (CSF); one of: sulphide treatment (ST); dimethyldithiocarbamate treatment (DT); carbonate treatment (CT); ethylenediaminetetraacetic acid treatment (EDTAT); organic extraction (OE); and recrystallization (RX). The present invention also pertains to the resulting (high purity) compounds, compositions comprising them (e.g., tablets, capsules), and their use in methods of inactivating pathogens, and methods of medical treatment and diagnosis, etc., for example, for tauopathies, Alzheimer's disease (AD), skin cancer, melanoma, viral diseases, bacterial diseases, or…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.