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Recently group of Erik 83 described a novel, short and efficient synthesis of diverse 2aminoimidazoles<br />

from readily available polysubstituted secondary propargylamines<br />

and thioureas (Scheme-1.9.1). Both the guanylation and the cyclization steps can be<br />

carried out either in a stepwise manner with a carbodiimide activator and an AgI<br />

catalyst or in a one-pot process with a recoverable AgI salt as a promoter and catalyst.<br />

This protocol was successfully applied to the total synthesis of all trisubstituted 2aminoimidazole<br />

naamine alkaloids. Furthermore, we demonstrated the potential of<br />

polysubstituted 2-aminoimidazoles as inhibitors of bacterial biofilm formation.<br />

R 1<br />

R 2<br />

R 3<br />

R 4<br />

Me<br />

CHO<br />

N<br />

H<br />

Boc<br />

N<br />

N<br />

Boc N<br />

Me<br />

N<br />

H2N N<br />

Me<br />

R 1<br />

R 1<br />

allyl<br />

R 5<br />

R 2<br />

R 4<br />

R 3<br />

1) TFA/DCM<br />

RT, 3h<br />

2) H2-Pd/C<br />

MeOH, RT<br />

R 5<br />

R 2<br />

R 4<br />

R 3<br />

R 5<br />

CuBr (10 mol %)<br />

100 oC, MW<br />

Toluene, 25 min<br />

6a<br />

AgNO3 (1.4 equiv)<br />

Et3N (2 equiv)<br />

MeCN, RT, 5 min<br />

Scheme 1.9.1 Short total synthesis of alkaloid of the naamine family<br />

R 1<br />

R 2<br />

R 1<br />

R 2<br />

R 3<br />

R 3<br />

R 4<br />

R 5<br />

N(Me)Allyl<br />

[Pd(PPh3) 4] (5 mol%)<br />

DMBA (3.5 equiv)<br />

DCM, Reflux, 25 min<br />

R 4<br />

NH(Me)<br />

R 5

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