Step 1: Install bootbox via npm install bootbox --save
Step 2: If you are using systemjs then include bootbox like:
<script src="node_modules/bootbox/bootbox.js"></script>
Step 3: Just put declare var bootbox:any; after import all libreries and before component decorator in your component ts file and then use normaly like bootbox.alert("Hello world!"); on any function call.
Make sure you have bootstrap and jquery installed and included in index page. jquery should be in first place then after bootstrap.
[Edit]
Alternate Step 3
Instead of declare var bootbox:any;, import type type definitions instead:
npm install @types/jquery --save
npm install @types/bootbox --save
