PROBLEM TO BE SOLVED: To obtain a new compound characteristic of a high-sensitive, high- selective and electrically neutral ionophore for ammonium ion, and useful as e.g. an ionically selective electrode for ammonium ion.
SOLUTION: This compound is shown by formula I (R1 to R10 are each H or a substituent; (n) is 0 to 2; (m) is 1 to 3; and (n+m)=3), e.g. [2,5,12,15,22,26- hexaoxaheptacyclo-[188.8.131.52.11.416.21.O1.27.O6.11. O16.21]tritetracontane. The compound is obtained by reacting an ethylene glycol derivative having a substituent with e.g. triethylene glycol and sequentially cyclizing it or by reducing a diacetal compound derived from malone aldehyde in the presence of metal hydride and cyclizing the thus obtained compound in the presence of e.g. substituted ethylene glycol.