Laboratory of Bioactive Natural Products Chemistry
Department of Material and Life Chemistry, Kanagawa University
Rm. 23-726 (laboratory), 23-727 (office), Kanagawa University,
3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama, 221-8686, Japan
Tel: +81-45-481-5661, ext. 3852 (laboratory), 3853 (office)Fax: +81-45-413-9770
E-mail: M. Okada: okada＠kanagawa-u.ac.jp
S. Akai: akais001＠kanagawa-u.ac.jp

Masahiro Okada(Professor)

Shoji Akai
(Associate Professor)---------------------------------------------------------------------------------------------------------------------------------------------------------------------------Research Field:

M. Okada: Natural Products Chemistry, Bioorganic Chemistry.
S. Akai: Organic Chemistry, Natural Products Chemistry, Carbohydrate Chemistry.

Research Overview: Bioactive natural products chemistry: discovery and identification, chemical synthesis, and elucidation ofbiosynthesis and function of biologically active natural products.
Research Highlights:
Studies of peptides post-translationally isoprenylated
at thetryptophan
residue
Post-translational
Isoprenylated
Peptidesat the Trp Residue

H 2N

HNO

H
N

H
N
H

O

O

H
N

NO

N
H

O

HN

CONH2
CO2H

CO2H
ComXRO-E-2 pheromone

HOH
HNNH2HOCO2H
HNH

H 2NONNOHNNOOComXnatto pheromone

ONH

NOOOO
N
HH
NNO

Total synthesis of bioactive natural compounds: The firststep in developing new medicines

CONH2O
N
H

OHN

HO2C
H2NOCHNNNH
HONH CONH2OO
NHO

CO2H
Kawaguchipeptin A

Proteins and peptides are biosynthesized through RNAtranslation, and RNA is produced through DNA transcription.
The plain proteins and peptides are generally inactive andfrequently chemically modified via post-translational
modification.
We have identified a new post-translation modification in apeptide pheromone, namely post-translational isoprenylationof the tryptophan residue. We are investigating the activation
mechanism, biological events, and universality of themodification.

The carbohydrates and amino acids we investigate in ourlaboratory are the most abundant compounds found inorganisms. They are commonly called sugars, starches, andproteins. Polysaccharides and polypeptides, which arecomposed of carbohydrates and amino acids, respectively,
play fundamental biological roles in living organisms.
Naturally occurring carbohydrates have a wealth ofstereochemical attributes. This research has been inspired bybiochemical mechanisms, and the need to discover new
antibiotics has driven research into the synthesis and chemical
modification of component sugar and amino acid units.

Publications:M. Okada: 1) T. Sugita, et al., A tryptophan prenyltransferase with broad substrate tolerance from Bacillus subtilis subsp. natto.
ChemBioChem, 2018, 19, 1396–1399. 2) M. Okada, et al., Combinatorial biosynthesis of (+)-daurichromenic acid and its
halogenated analogue, Org. Lett. 2017, 19, 3183-3186. 3) M. Okada, Posttranslational isoprenylation of tryptophan in bacteria",
Beilstein J. Org. Chem. 2017, 13, 338–346.
S. Akai: 1) S. Akai, et al., Stereocontrolled total synthesis of tetrodotoxin from myo-inositol and D-glucose by three routes:
Aspects for constructing complex multi-functionalized cyclitols with branched-chain structures, Nat. Prod. Commun., 2015, 10(5),691-702. 2) S. Akai, et al., A concise total synthesis of (+)-pancratistatin from D-glucose featuring the Henry reaction”, Asian J.
Org. Chem., 2013, 2, 299-302.
Affiliated Academic Organizations:M. Okada: The Japan Society for Bioscience, Biotechnology, and Agrochemistry; The Chemical Society of Japan; The
Pharmaceutical Society of Japan; American Chemical Society; The Japan Society of Pharmacognosy.
S. Akai: The Chemical Society of Japan; The Society of Synthetic Organic Chemistry, Japan; The Japanese Society ofCarbohydrate Chemistry; American Chemical Society.
---------------------------------------------------------------------------------------------------------------------------------------------------------Current Members: Professor; Associate Professor, and Undergraduates: 9 (2018.04.01)
Facilities: Microwave synthesizer, HPLC system.