British startup Synthesia, whose AI platform helps companies create interactive training videos, has raised a $200 million Series E round of funding that brings its valuation to $4 billion — up from $2.1 billion just a year ago. Unlike some other AI startups that are still a long way from turning a profit, Synthesia has found a lucrative business in transforming corporate training thanks to AI-generated avatars. With enterprise clients including Bosch, Merck, and SAP, the London-based company