Help with macros

Hello all, I have just switched to razer from corsiar and need help making some custom macros. I understand the basics of macros, I just need to know how to do the following: I want to make a macro where I press a button on my mouse and the macro presses the "1" key on the keyboard, then it releases the "1" key on the keyboard when I let go of the mouse button. I dont want it to release the "1" key until I release the mouse button. Is this possible with Razer Synapse? For context, I'm a smite player and I want the ability targeter to show up when the mouse button is pressed, but not actually fire the ability until i release the mouse button.