Scroll button on Logitech mouse won't left/right "click"
Apple offers basic mouse support out of the box for just about any USB or Bluetooth mouse. However, the center button's right/left clicks are not considered standard mouse functionality. Therefore in order to utilize these buttons, a driver or special piece of software is required. Unfortunately Logitech does not provide any special software compatible with both the Mac and the mouse model you have. This support thread on Logitech's site includes a comment from a Logitech employee confirming this.

I have seen reports that Better Touch Tool supports certain Logitech models, to fill in the gaps that Logitech left in designing this mouse. It's worth a download, as it's free.