56205-54-0Relevant academic research and scientific papers
Exothermic thermal reaction of dopamine with 3,5-dinitrobenzoic acid
Ito, Yoshikatsu,Arimoto, Satoru
, p. 849 - 857 (2003)
Pyrolysis of the crystalline 1:1 molecular complex DA·dnba, which was prepared from cocrystallization of dopamine (DA) and 3,5-dinitrobenzoic acid (dnba), was studied. This cocrystal decomposed violently at the melting-point, leading to the formation of a black solid along with a tiny amount of 3-amino-5-nitrobenzoic acid (1). The pyrolysis reaction was followed by differential scanning calorimetry (DSC) and one large exothermic peak was observed at the decomposition temperature. In view of the DSC patterns for cocrystal DA·dnba and other compounds, it seems that both a catechol moiety and an amino group of DA in addition to a strong electron acceptor such as dnba are required for the appearance of the exothermic peak. On the basis of (a) elemental analysis of the black solid and (b) other pyrolysis experiments for cocrystals PA·dnba (PA: β-phenylethylamine), BA·dnba (BA: benzylamine), DMDA·dnba (DMDA: O,O′-dimethyldopamine) and DHBA·dnba (DHBA: 3,4-dihydroxybenzylamine), it is assumed that the black solid was formed mainly through elimination of more than one molecule of water from one molecule of DA·dnba. Copyright
Structural optimization of natural product nordihydroguaretic acid to discover novel analogues as AcrB inhibitors
Alenzy, Rawaf,Liu, Xingbang,Ma, Shutao,Ma, Yingang,Mowla, Rumana,Polyak, Steven W.,Song, Di,Teng, Yuetai,Venter, Henrietta,Wang, Yinhu
, (2019/12/24)
Drug efflux pumps confer multidrug resistance to dangerous bacterial pathogens which makes these proteins promising drug targets. Herein, we present initial chemical optimization and structure-activity relationship (SAR) data around a previously described efflux pump inhibitor, nordihydroguaretic acid (NDGA). Four series of novel NDGA analogues that target Escherichia coli AcrB were designed, synthesized and evaluated for their ability to potentiate the activity of antibiotics, to inhibit AcrB-mediated substrate efflux and reduce off-target activity. Nine novel structures were identified that increased the efficacy of a panel of antibiotics, inhibited drug efflux and reduced permeabilization of the bacterial outer and inner membranes. Among them, WA7, WB11 and WD6 possessing broad-spectrum antimicrobial sensitization activity were identified as NDGA analogues with favorable properties as potential AcrB inhibitors, demonstrating moderate improvement in potency as compared to NDGA. In particular, WD6 was the most broadly active analogue improving the activity of all four classes of antibacterials tested.
