Natural Medicines

Humans have been using plants, mushrooms, and other organisms as medicines since ancient times. In fact, many medicines have been developed from natural compounds produced by plants, fungi, bacteria, and other microorganisms. Thus, natural compounds are the resources for drug discovery.

We conduct research to find natural product that can be used as resources for drug discovery, or to create them using natural compounds as motifs. In addition, we aim to use the substances obtained as seed compounds for the development of pharmaceuticals, as well as for the development of substances useful for life science research.

On the other hand, as a result of the vigorous search for natural compounds, new natural compounds are being depleted. Therefore, it is not possible to conduct innovative drug discovery research by simply searching for natural compounds in the conventional way. Therefore, we will actively explore new resources for drug discovery.

Diversity-oriented synthesis is a synthetic method for producing a large number of compounds with different molecular skeletons from a single starting material. In particular, "diversity-enhanced extracts," which combine diversity-oriented synthesis with search for natural compounds, can yield a group of new compounds with structural diversity that exceeds that of natural compounds obtained from plants and microorganisms. We will conduct research to utilize these compounds as resources for drug discovery.

For example, we will perform chemical reactions directly on the extracts of medicinal plants used as crude drugs, as used in diversity-directed synthesis, to produce diversity-enhanced extracts. By separating, purifying, and structurally determining these extracts, we can construct a library of structurally diverse compounds and obtain seed compounds for drug discovery research.

As a new drug discovery resource, we will focus on " unexploited organisms" which are different from conventionally used organisms, such as plants, fungi, and bacteria, for the search of natural compounds. Particularly, we will focus on protists, which are extremely diverse organisms that span multiple biological kingdoms, and utilize unexploited organisms such as cellular slime mold, oomycetes, and pelagic algae. In fact, compounds obtained from cellular slime mold have been developed as commercially available reagents for life science research. Thus, these unexploited organisms, including cellular slime mold, are considered to have great potential as new resources for drug discovery.

Extracts of plants and microorganisms are multicomponent systems containing various compounds, and it is not easy to obtain structural information and quantities of all the compounds contained. We have developed molecular networking based on compound data obtained by simultaneous multi-component analysis using LC-MS/MS, which enables visual understanding of compound profiles in multi-component systems. In addition, by efficiently eliminating known compounds (dereplication), we are able to rapidly discover new compounds and estimate their structures. By applying this analytical platform, for example, we are searching for new compounds produced by cyanobacteria, determining the quality of crude drugs, and analyzing compound-compound interactions in multicomponent systems.