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Structure of prolylrapamycin: confirmation through a revised and detailed NMR assignment study
Annalisa Mortoni1, Eugenio Castelli2, Teresa Recca3
1Curia Italy S.r.l., Via Volturno 43, 20089, Rozzano, MI, Italy. annalisa.mortoni@curiaglobal.com.
The Journal of Antibiotics
|March 20, 2024
Summary
Detailed characterization of Rapamycin and Prolylrapamycin using advanced spectroscopic methods confirmed Prolylrapamycin
Area of Science:
- Chemical characterization
- Spectroscopic analysis
- Organic chemistry
Background:
- Rapamycin is a known immunosuppressant drug.
- Structural modifications of Rapamycin are explored for new properties.
- Sirolimus is the generic name for Rapamycin.
Purpose of the Study:
- To fully characterize Rapamycin and Prolylrapamycin.
- To confirm the structural differences between Rapamycin and Prolylrapamycin.
- To utilize advanced analytical techniques for molecular identification.
Main Methods:
- Homo- and hetero-nuclear Nuclear Magnetic Resonance (NMR) experiments.
- High-Resolution Mass Spectrometry (HRMS).
- Fourier-Transform Infrared (FT-IR) spectroscopy and Differential Scanning Calorimetry (DSC).
Main Results:
- Complete assignment of proton and carbon atoms for both Rapamycin and Prolylrapamycin.
- Definitive confirmation of a pyrrolidine ring in Prolylrapamycin.
- Distinction from the piperidine ring found in Sirolimus (Rapamycin).
Conclusions:
- The structural integrity and modifications of Rapamycin derivatives are elucidated.
- NMR spectroscopy is a powerful tool for detailed structural elucidation.
- Prolylrapamycin possesses a distinct structural feature compared to Rapamycin.
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