Unable to resolve dependencies (gradle)

We recently setup nexus respository on one of our aws ec2 accounts and to test the repo, we uploaded a jar file and tried using that jar in my build.gradle file. But seems like gradle is unable to find the artifact. I am getting the following error: Declare repository providing the artifact, see the documentation at Declaring repositories

Attached is the screenshot of my simple build.gradle file

Is there any other setup to be done before i can start resolving those dependencies? do let me know.

This is my nexus page