Synthetic antispasmodics. I. Some new basic esters

The Polymorphism of 2-Benzoyl-N,N-diethylbenzamide

“…This result is similar to the melting point of the sample first synthesized by Projotiva et al (51.5 °C). Thus, identified here is the form synthesized by Projotiva et al as form II [13]. In the second heating cycle, most of form II is amorphous, and it is possible to observe the glass transition temperature at −20.8 °C and a small endothermic peak with an onset of 53.9 °C, still consistent with the melting of form II.…”

“…Synthesis was performed using the route described by Wei et al (2015), and details of the synthesis, as well as 1 H and 13 C NMR spectra of BDB are available in the Supporting Information (Scheme S1, Figures S1 and S2) [20].…”

“…2-benzoyl-N,N-diethylbenzamide was synthesized in 77% yield following the procedure described in the Supporting Information, Scheme S1. 1 H and 13 C NMR spectra of BDB were obtained, and details are available in Figures S1 and S2.…”

“…There is no evidence that the formation of a preferential form of BDB can result from the recrystallization method used, as this compound was crystallized using different routes when the melting point of the compound was also reported [13,14,19]. Sakamoto and co-workers reported the form I was prepared from a 1:1 mixture of hexane and chloroform, a solvent mixture also suitable to recrystallize form II [15].…”

“…The compound studied in this work, 2-Benzoyl-N,N-diethylbenzamide (BDB, Scheme 1), was first reported by Projotiva et al (1950) as a potential candidate for antispasmodic drugs [13]. The compound was synthesized and thermally characterized, where the obtained melting point was 51.1 • C. A year later, thermal characterization of BDB was performed by Linn et al (1951) prior to reactions between a series of N,Ndiethylbenzamides and sodium, where the author found a higher melting point for the compound (MP = 76-77 • C), showing a possible new form of BDB [14].…”