An Antimalarial Alkaloid From Hydrangea. Iv. Functional Derivatives of 3-Alkyl-4-Quinazolones

Abstract

Early degradation experiments on the Hydrangea alkaloid (1) indicated that this molecule was a derivative of 4-quinazolone with a side chain on the 3-position containing one basic nitrogen and two oxygens. With this limited information on hand a number of 3-alkyl-4-quinazolones with functional groups in the side chain were synthesized in order to obtain (a) suitable models for degradation experiments (l), (b) compounds to be tested for antimalarial activity,' and (e) information on the synthesis and transformations of these functional groups.2There are a number of methods described in the literature for the synthesis of molecules of this type, three of which were employed. Clark and Wagner (7) ha,ve heated primary aromatic amines with isatoic anhydride (I) and ethyl orthoformate to form 3-aryl-4-quinazolones (11). This procedure has now been 0 0 0

A Novel Synthesis of the Efficient Anti-Coccidial Drug Halofuginone Hydrobromide

“…The preparation of piperidine analogues was the most expensive part, and deemed to be the real difficulty to produce halofuginone as well. So far, a lot of methods have been reported: The method illustrated in Scheme 3 was originally developed by Baker’s team [ 18 , 22 , 23 , 24 , 25 , 26 ]. Afterwards, the method was optimized a bit by Barringer et al, via changing reagents and catalyst, which successfully improved the yield by reducing the number of steps but without lowering the cost.…”

Regioselective synthesis of N(3)‐ and O‐acylmethyl derivatives of 2‐methylthio‐4(3H)‐quinazolinone

“…The quinazolinone skeleton is considered to be a privileged structure and has been utilized as a druglike scafold in medicinal chemistry [4]. N (3) -Substituted 4(3H)-quinazolinones show antimalarial [5][6][7][8][9], anti-inflammatory and antitumor [10] activities. A derivative of (N (1) -quinazolinyl)acetic acid Zanerestat is a remedy of diabetic complications [11].…”

Synthesis and intramolecular cyclization of 2‐methylsulfany‐4‐oxo‐3(4H)‐quinazolinyl)acetohydrazide

“…4(3H)-Quinazolinones, particulary those N (3) -substituted, have been attracting attention for a few decades and have renewed continuing interest in recent years due to their multitude important activities. Febrifugine as a representative of N (3) -substituted 4(3H)-quinazolinones is known to be highly active against malaria [7][8][9][10][11]. 4(3H)-Quinazolinone N (3) -alkanoic acid derivatives exhibit antiinflammatory, antitumor [12], analgetic [13], antihistaminic [14], fungicidal or plant growth regulator properties [15,16].…”