Microsoft Graph (https://graph.microsoft.io/) is an interesting platform that provides a unique gateway for RESTful APIs that spans multiple Microsoft services. Dynamics 365 Business Central is now one of the endpoints available in Microsoft Graph.
To work with Dynamics 365 Business Central in Graph, you first need to change your Dynamics 365 Business Central user's permission in Graph and then enable the Financials.ReadWrite.All permission scope. You can do that by using the Graph Explorer tool:
After setting the permissions, you can start using the Dynamics 365 Business Central APIs available in Graph (actually, you need to use the BETA API endpoint).
As an example, to retrieve the available companies in your Dynamics 365 Business Central tenant...