Furancarbonylguanidine derivatives, their preparation and pharmaceutical compositions containing them

A method for preparing a furancarbonylguanidine compound of Formula 1, as shown in Scheme 1, comprising:

• reacting a carboxylic acid derivative compound of Formula II with guanidine in the presence of base or with an excess amount of guanidine
• wherein
• R1 and R2 are each independently H, F, Cl, Br, I, CF3, SO2CH3, NO2, NH2, C1˜C5 straight or branched alkyl, or ORa;
• Ra is H, CF3, C1˜C5 straight or branched alkyl, or phenyl;
• and
• L is a leaving group that is easily left by guanidine.

A method for preparing a furancarbonylguanidine compound of Formula 1, as shown in Scheme 2, comprising:

• reacting a carboxylic acid compound of Formula III with guanidine in the presence of a condensation agent
• wherein
• R1 and R2 are each independently H, F, Cl, Br, I, CF3, SO2CH3, NO2, NH2, C1˜C5 straight or branched alkyl, or ORa;
• Ra is H, CF3, C1˜C5 straight or branched alkyl, or phenyl.

A method for preparing a furan compound having a benzene ring at the 5th site, as shown in Scheme 3a, comprising:

• reacting a phenylboronic acid or stanylphenyl derivative compound of Formula IV with a 5-halofuran compound of Formula V in the presence of a palladium catalyst, which is a Stille-type coupling or Suzuki-type coupling, to form a compound of Formula II1
• wherein
• R1 and R2 are each independently H, F, Cl, Br, I, CF3, SO2CH3, NO2, NH2, C1˜C5 straight or branched alkyl, or ORa;
• Ra is H, CF3, C1˜C5 straight or branched alkyl, or phenyl;
• X is B(OH)2, BCl2, BBr2, SnBu3, SnMe3, or ZnCl, and
• Y is a halogen or OSO2CF3 wherein the halogen is Br, I or Cl.