Insights in the vibrational optical activity spectra of the antibiotic vancomycin in DMSO

Abstract

Vibrational circular dichroism (VCD) and Raman optical activity (ROA) are two spectroscopic techniques that are sensitive towards the conformational behaviour of molecules, and are often complementary herein. In this work...

Vibrational Optical Activity Study of Four Antibiotic (Lipo)glycopeptides: Vancomycin, Oritavancin, Dalbavancin, and Teicoplanin

“…When the calculated Raman and ROA spectra of vancomycin, oritavancin, and dalbavancin, shown in Figure (1150–1800 cm –1 ) and Figure S3 (Supporting Information; 500–1800 cm –1 ), are inspected, a good visual match is found with the corresponding experimental recordings for vancomycin and dalbavancin. This is confirmed by an overlap integral, calculated over the spectral region of 500–1800 cm –1 , close to 0.8 and 0.5 for the Raman and ROA spectra, respectively, values that are considered adequate for this molecular class. , The calculated ROA spectrum of oritavancin deviates stronger from the experiment ( S fg = 0.18). The conformation of the molecular scaffold of oritavancin, however, will not differ significantly from that of vancomycin.…”

“…Their intensities appear to respond foremost to the chemical content of each compound and respond less to the conformation adopted. This too was concluded in the past for vancomycin. , The current study hence demonstrates how they are complementary between the chiral and nonchiral spectroscopic techniques and that this is not a matter of superiority of one or the other type of spectroscopy.…”

“…This too was concluded in the past for vancomy-cin. 24,25 The current study hence demonstrates how they are complementary between the chiral and nonchiral spectroscopic techniques and that this is not a matter of superiority of one or the other type of spectroscopy.…”

“…This is confirmed by an overlap integral, calculated over the spectral region of 500− 1800 cm −1 , close to 0.8 and 0.5 for the Raman and ROA spectra, respectively, values that are considered adequate for this molecular class. 24,25 The calculated ROA spectrum of oritavancin deviates stronger from the experiment (S fg = 0.18). The conformation of the molecular scaffold of oritavancin, however, will not differ significantly from that of vancomycin.…”

“…In this contribution, we extend the investigation toward several derivatives so as to gain a deeper insight into what the VOA techniques can or cannot tell us about glycopeptide antibiotics. Three derivativesoritavancin, dalbavancin, and teicoplaninwere selected as subjects of this study (see Figure ) based on findings for vancomycin: the domination of the aromatic part in the VOA intensities and the invisibility of the carbohydrate entities. , Oritavancin and dalbavancin are registered as treatment drugs against skin infections since 2014, whereas teicoplanin was approved in 1988 in Europe as a treatment against, among others, bone and soft tissue infections. , All of the derivatives consist of additional aromatics systems: oritavancin contains a flexible chlorobiphenylmethyl group attached to the 4- epi -vancosamine carbohydrate, while dalbavancin and teicoplanin possess two additional aromatic rings that constitute an additional cycle between the first and third amino acids in the peptidic backbone. Oritavancin has an additional aminated sugar attached to the sixth amino acid.…”