American Well Corp. , known as Amwell, said late Wednesday that its upsized initial public offering priced at $18 a share, above the expected range of between $14 and $16 a share, as the Boston-based telemedicine company raised $742 million. The company, which is being backed by Alphabet Inc.’s Google, sold 41,222,222 Class A shares in the IPO, up from previous expectations of 35,000,000 shares. If the underwriters exercise all the options to buy up to 6,183,333 additional shares to cover overallotments, the company could raise $853.3 million. The company has 187,432,130 Class A shares, and a total of 220,164,563 Class A, Class B and Class C shares outstanding after the IPO, which at the IPO price would be valued at $3.96 billion. The stock is slated to begin trading Thursday on the NYSE under the ticker symbol “AMWL.” The company is going public during a busy week for IPOs, but investor demand appears to remain high as the Renaissance IPO ETF has rallied 23.7% over the past three months while the S&P 500 has gained 8.7%.Market Pulse Stories are Rapid-fire, short news bursts on stocks and markets as they move. Visit MarketWatch.com for more information on this news.