Datasync cannot configure scheduled tasks with an interval less than 60 minutes?

I suggest to look at AWS DataSync documentation and use cases to see if it is the right fit solution for your 5 minutes use case. https://aws.amazon.com/datasync/faqs/

Still if you need AWS DataSync to run every 5 minutes, see if below helps once your DataSync task is configured:

1. Create a AWS Lambda to trigger AWS DataSync task
2. Automate AWS Lambda to start based on some event e.g. Amazon EventBridge can be configured to run this AWS Lambda every 5 minutes.

One reference implementation of event based triggering of AWS DataSync using AWS Lambda, where AWS DataSync task is triggered both as per schedule as well as AWS Lambda based on event. https://aws.amazon.com/blogs/storage/event-driven-data-transfer-to-container-shared-storage-on-aws/