RUDN University chemist developed green method for malaria and leprosy drug production - EurekAlert

-
IMAGE

IMAGE: A chemist from RUDN University suggested an eco-friendly method for the synthesis of dapsone, a substance that inhibits the growth of malaria and leprosy agents. The main component of the... view more 

Credit: RUDN University

A chemist from RUDN University suggested an eco-friendly method for the synthesis of dapsone, a substance that inhibits the growth of malaria and leprosy agents. The main component of the new reaction is hydrogen peroxide that does not form environmentally destructive compounds, and the only by-product is simple water. Unlike other technologies, this method includes only one stage of dapsone production and does not require high temperatures. The catalyst of the reaction can be reused without any loss of efficiency. The results of the work were published in the Microporous and Mesoporous Materials journal.

Many think of leprosy as a disease of the past; however, about 200 thousand cases of it are registered in the world (mainly in India, Brazil, and Nepal) every year. It is treatable with antibiotics that prevent the growth of the Mycobacterium bacteria. On the contrary, malaria is one of the most widely spread diseases in the world with over 200 million cases annually. The spread of its agent (a protist from the genus Plasmodium) also can be inhibited with antibiotics. Dapsone is a safe and available drug that works in both cases and is included in the WHO Model List of Essential Medicines. However, its production is not eco-friendly, as the synthesis reaction requires high temperatures and the use of aggressive acids (such as sulphuric acid). A chemist from RUDN University suggested a green technology of dapsone synthesis that could potentially help expand its production and make the drug available to more patients.

Dapsone or diaminophenyl sulphone consists of two benzene rings with NH2 amino groups. The rings are connected with an oxidized atom of sulfur, or an SO2 group. To obtain dapsone, manufacturers oxidize its precursor in which the bond between the rings is formed by an SH group (sulfur and hydrogen). However, oxidation can also affect sensitive amino groups. Therefore, they have to be protected before the reaction starts--for example, by attaching special protective groups to them. The researcher from RUDN University developed a catalyst that provides for the oxidation of SH groups in the precursor with simple hydrogen peroxide. Hydrogen peroxide is considered the most environmentally friendly oxidizing agent because its only by-product is water. The reaction of oxidation takes place at room temperature, has only one stage, and requires no protection of amino groups.

"None of the earlier dapsone synthesis reactions can be called completely environmentally friendly as they happen in rigid conditions and have several stages: adding protective groups, synthesis, and their removal. This complexity increases the chances of by-products that should be removed from the reaction," said Raphael Luke, Ph.D., the head of the Molecular Design and Synthesis of Innovative Compounds for Medicine Science Center at RUDN University.

His team developed a wolfram-based catalyst from polyoxometalates by replacing certain wolfram atoms with vanadium. This increased the acidic properties of the catalyst and sped up the reaction, allowing it to take place even at low temperatures. To prevent the catalyst from being washed off from the reaction, the chemists encased the new compound in a porous material--a hydrogel made of propanoic acid and acrylamide. Thanks to it, the catalyst can be re-used at least three times without losing its efficiency. The team also identified the most optimal synthesis conditions and reagent concentration and managed to reach 100% oxidation of the dapsone precursor at 25? in only nine hours.

###

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.



Comments

Post a Comment

Popular posts from this blog

Manual on meat inspection for developing countries

-
Image
sinusitis treatment :: Article Creator My 'sinus Infection' Turned Out To Be A One In A Million Nasal Cancer At Just 28 - And Doctors Had To Cut My Eye Out To Save Me By Emily Joshu Health Reporter For Dailymail.Com Published: 06:33 EDT, 20 April 2024Updated: 06:35 EDT, 20 April 2024 A 28 year-old California woman has described the shock of being diagnosed with a deadly sinus cancer that affects fewer than one in a million people - and led to the removal of her right eye. The 'golf ball-sized tumor', which had spread throughout her face, was first mistaken for a sinus infection by the woman's doctors.  Annika, who posts about her condition on TikTok, woke up one morning in 2023 and noticed that the inner corner of her right eye was sore.  While she at first thought nothing of it, by the time the evening rolled around, 'my face started to really, really hurt on the right side,' she said in a video.  The next day, her...
Read more

Rash behind ear: Causes, other symptoms, and treatment - Medical News Today

-
Image
A rash behind the ear may occur due to a variety of different medical conditions. Certain viral infections and autoimmune diseases may cause a rash behind the ear in both children and adults. While some causes, such as contact dermatitis, are not concerning, other causes, including rubella, may be more serious. In this article, we look at some of the causes of a rash behind the ear, as well as the other symptoms that they may produce and how to treat them. Contact dermatitis is an allergic reaction to a particular substance. If an allergy-inducing substance comes into contact with the skin behind the ear, a rash can form. Allergens that may cause contact dermatitis behind the ears include: shampoos soaps other hair care products For example, hair dye products contain an ingredient called paraphenylenediamine (PPD), which is a common contact allergen. Symptoms Contact dermatitis causes itchiness, dryness, and flaking of the skin that came into contact with the allergen. Diagnosis A doc...
Read more

Freddie Mercury's haunting last picture before tragic death from Aids - Irish Mirror

-
Freddie Mercury's final days in 1991 remain enshrined in mystery, nearly 30 years on. The Queen frontman succumbed to his battle with Aids on November 24, having released a public statement just 24 hours previously that confirmed he was HIV+. Rumours had been swirling about his health status for a number of years, with speculation that he had been tested for HIV and Aids as far back as 1986, after his health declined so rapidly that Queen had to halt their 1987 Magic Tour before it was due to finish. Freddie, real name Farrokh Bulsara, had been something of a recluse in his last two years, preferring to stay at his lavish Garden Lodge home in west London's Kensington than rub shoulders with other celebrities at showbiz parties. Tragically, Freddie's health continued to deteriorate in private, as feverish speculation mounted that he was gravely sick. The last known photos of him show how much weight he had lost during his rare public appearances towards the end. On Sep...
Read more