Structural analysis of photo-degradation in thiazole-containing compounds by LC–MS/MS and NMR

A critical review on the use of modern sophisticated hyphenated tools in the characterization of impurities and degradation products

“…More specific applications of 1D and 2D LC-NMR in understanding inherent degradation behavior of APIs and the formation of DPs in formulations were critically described by Pan et al [103]. There are several other reports on the use of LC-NMR for structural characterization of IMPs and degradation/interaction products [39,122,153,168,[225][226][227][228][229][230][231][232][233][234][235][236][237][238][239][240][241][242]. A compilation is separately given in Table S4, which includes details of drugs/compounds investigated, IMPs/DPs characterized, their amount in the sample, instrument configuration, operation mode, etc.…”

Photodynamic Therapy for Cancer and for Infections: What Is the Difference?

“…[55] Secondly, 1 O 2 may participate in Diels-Alder cycloadditions, resulting in the formation of bridged endoperoxides. [56] The third type is the addition of 1 O 2 to an activated carbon-carbon double bond to form an unstable 1,2-dioxetane ring system.…”

Identification of Pharmaceutical Impurities in Formulated Dosage Forms

“…In many cases, the combination of both techniques could increase identification confidence. [84][85][86][93][94][95][96] One example is shown in a mass spectrum acquired from an ion-trap MS, in which the protonated molecular ion of an unknown peak appeared to be at m/z 214 (Figure 15a). However, the m/z 214 ion was also present as a strong background accurate mass results and the drug substance structure, the unknown compound was readily identified as a drug degradation product, resulting from the dealkylation of the drug substance.…”