- One-pot green synthesis of β-artemether/arteether
-
An efficient one pot green synthesis of β-artemether/arteether from artemisinin has been developed using a sodium borohydride-cellulose sulfuric acid (CellSA) catalyst system. The green methodology is high yielding and the catalyst has good recyclability.
- Kumar, Atul,Bishnoi, Ajay Kumar
-
p. 31973 - 31976
(2014/08/18)
-
- New method for the synthesis of ether derivatives of artemisinin
-
Dihydroartemisinin can be converted to its ether derivatives in good yields by reaction with different alcohols in the presence of a catalytic amount of dodecatungstophosphoric acid hydrate. Easy handling, trouble-free workup by filtration, excellent yields, and very short reaction times are some of the highlights of this protocol. Copyright Taylor & Francis Group, LLC.
- Bora, Pranjal P.,Baruah, Nabajyoti,Bez, Ghanashyam,Barua, Nabin C.
-
p. 1218 - 1225
(2012/04/04)
-
- PREPARATIVE PROCESS FOR ETHER DERIVATIVE OF ARTEMISININ
-
The present invention relates to a process for synthesis of ether derivative of artemisinin by reducing artemisinin to dihydroartemisinin using a mixture of sodium borohydride and a dihydroxy compound, followed by etherification in presence of an acid catalyst and an alcohol.
- -
-
Page/Page column 11; 12; 14; 15
(2008/12/07)
-
- SINGLE POT CONVERSION OF ARTEMISININ INTO ARTEETHER
-
The present invention provides a method for the preparation of arteether from artemisinin in one pot in just about 4 hours comprising reduction of artemisinin into dihydroartemisinin by less quantity of sodium borohydride in ethanol at room temperature in the presence of a novel polyhydroxy catalyst, acylation of dihydroartemisinin in the presence of an acid catalyst, extraction of arteether from an aqueous reaction mixture using 1% ethyl acetate in n-hexane followed by workup and purification of the impure arteether to yield 80-86% (w/w) pure alpha, beta arteether.
- -
-
-
- An improved procedure for the synthesis of ethers of dihydroartemisinin
-
A simple and efficient method for the preparation of ethers (3a-f) of dihydroartemisinin (2) has been developed using chlorotrimethylsilane as a catalyst.
- Bhakuni, Rajendra S.,Jain, Dharam C.,Sharma, Ram P.
-
p. 529 - 530
(2007/10/02)
-
- Anhydrous ferric chloride, a reagent for epimerisation of β-arteether to α-arteether
-
Artemisin is the first non-nitrogenous antimalarial compound having a 1,2,4-trioxane group which is responsible for its antimalarial activity.Our studies have shown that the activity of the β-arteether (1) as fast acting antimalarial is comparable to that of a 70 : 30 mixture of β- and α-arteethers (1 and 2) which are developing as a new drug.In continuation of our search for new reagents for the epimerisation of β-isomer (1) to β,α mixture (1 and 2) it was found that FeCl3 in CH2Cl2 at 0 deg C was very effective.This reagent offers a simple route to convert β-isomer (1) to α-isomer (2) becouse it is inexpensive and epimerisation is fast.
- Pathak, Ashish K.,Jain, Dharam C.,Sharma, Ram P.
-
-
- Arteether, a new antimalarial drug: Synthesis and antimalarial properties
-
Arteether (6) has been prepared from dihydroqinghaosu (3) by etherification with ethanol in the presence of Lewis acid and separated from its chromatographically slower moving α-dihydroqinghaosu ethyl ether (7). The absolute stereochemistry at C-12 has been determined by 1H NMR data (J11,12, NOESY). Ethyl ethers 6 and 7 showed potent in vitro inhibition of Plasmodium falciparum, and both compounds were highly potent antimalarials in mice infected with a drug-sensitive strain of Plasmodium berghei. Crystalline arteether (6) and its oily epimer 7 were 2-3 times more potent schizontocides than qinghaosu (1), but deoxy compounds 8, 9, and 11 were 100-300 times less potent in vitro than their corresponding peroxy precursors. Pharmacological studies have shown arteether (6) to have antimalarial activity in animals comparable to artesunate (2) and artemether (4), both of which are fast-acting blood schizontocides in humans. Arteether (6) has now been chosen for a clinical evaluation in high-risk malaria patients.
- Brossi,Venugopalan,Gerpe,Yeh,Flippen-Anderson,Buchs,Luo,Milhous,Peters
-
p. 645 - 650
(2007/10/02)
-