In the late 1950s and 1960s, thalidomide, a drug given to pregnant women to alleviate morning sickness, caused a tragic outcome. Over 12,000 babies were born with severe malformations, like shortened limbs, due to the drug’s side effects. These deformities were caused by the drug’s racemic mixture of two mirror-image forms. Understanding the molecular structures of compounds is vital for comprehending biological processes and developing effective drugs. Nuclear magnetic resonance spectroscopy (NMR) plays a significant role in this research by interpreting frequency signals. However, until recently, selectively measuring carbon nuclei signals associated with specific hydrogen atoms in a single measurement posed a challenge.
However, there is good news. Doctors in Korea have introduced a groundbreaking NMR method called the ultraselective heteronuclear polarization transfer method (UHPT). Before the UHPT method, NMR equipment allowed for selective measurement of specific hydrogen nuclei signals but lacked rapid measurement of carbon nuclei signals, leading to unsatisfactory resolution of hydrogen-carbon NMR signals. Additionally, it hindered the identification of chemical structures in pharmaceutical raw materials and potentially toxic drugs.
Thanks to the UHPT method, the doctors successfully distinguished carbon nuclei associated with specific hydrogen atom nuclei in a single measurement, even amid complex carbon-carbon NMR signals, achieving a signal resolution of several hertz (Hz). They used this method to analyze the structures of complex natural products like the anticancer drug dactinomycin, which comprises optical isomers of amino acids, and accurately assign the structure of the fungicide iprovicarb, a mixture of diastereoisomers.
This novel method is not only faster and more accurate than conventional approaches but also economically efficient. The UHPT method significantly reduces the measurement time needed for ultra-high field NMR equipment, achieving equivalent NMR signal resolution approximately one-fifth of the time.
As per insights, this new NMR method can become a standard analysis technique for identifying and standardizing active ingredients in the natural product bio industry. By using this method to identify the structure of partial particulate matter, which plays a crucial role when it comes to determining the efficacy and safety of drugs, it is expected to contribute significantly to the development of the natural product bio industry and address challenges in drug development processes.