How to specify c:\program files (x86) on command line

I have the following but can't get beyond the stupid whitespace in "c:\Program Files (x86)" to run msbuild.exe. Someone please help. This sort of thing should be covered in the documentation. All the YAML lint tools I find say that this is perfectly valid.

stages:
  - build

compile:
  stage: build
  script:
    - c:\nuget\nuget.exe restore
    - c://Program Files (x86)//MSBuild//14.0//bin//msbuild.exe mrakOcu.sln /t:applications\mrakOcu /p:Configuration=Release;Platform="Any Cpu" /consoleloggerparameters:ErrorsOnly /verbosity:quiet