JSFiddle - React, Tailwind, and code Playground

JavaScript

var items = [
   {
      "Id":{
         "LValue":1,
         "Value":1
      },
      "Date":{
         "LValue":"2013-10-17T00:00:00",
         "Value":"2013-10-24T00:00:00"
      },
      "User":{
         "LValue":508,
         "Value":507
      },
      "Comments":{
         "LValue":"This a test load",
         "Value":"This a test"
      },
      "Name":"John Doe",
      "IsDeleted":false
   }
];

var flattenedItems = items.map(function(x) {
    return {
        Id: x.Id.Value,
        Date: x.Date.Value,
        User: x.User.Value,
        Comments: x.Comments.Value,
        Name: x.Name,
        IsDeleted: x.IsDeleted,
        LValues: {
            Id: x.Id.LValue,
            Date: x.Date.LValue,
            User: x.User.LValue,
            Comments: x.Comments.LValue,
        }
    };
});
console.log(flattenedItems);