Flag cells with data that ends with alpha characters

Flag in an adjacent cell only the text strings below that contain ending alpha characters that are not preceded by space(s). For example, I only want to flag numbers 2.), 4.) and 6.).
1.) 4 P-17093
2.) 2 P-17094A
3.) P-17094 E
4.) P-17094D
5.) 7 P-17095 E
6.) 8 P-17095C

=if(isnumber(1*right(cell being checked,1)),"Do Not Flag","Flag")

Then put a simple conditional format if you want to color code it.