Is this a product with any volume or a one-off?
The first stage is easy and there should be readily available modules/designs to handle it:
**broken link removed**
The second leap is a bit harder. Few off the shelf modules or designs output 380. 'PFC' modules do but they expect 90 in or close too it. The linked module go can up to 48V out but won't get you to 90.
But still, although labeled as AC-DC boosting PFC's are really a rectifier then DC-DC boost. So my thought is you could adapt a PFC module or reference design to run continuously off 48V fairly easily.