Synplicity ( SYNP) plummeted more than 27% in after-hours trading Thursday as the Sunnyvale, Calif.-based company guided lower than its previous forecast and below Wall Street expectations as well. The semiconductor-software company now expects revenue of $16.4 million for the Dec. 31, 2006, quarter, down from its previous range of $17.2 million to $17.7 million. Analysts polled by Thomson Financial are seeking $17.5 million. In addition, the company shaved a penny off the top of its earnings range, now expecting between 6 cents and 7 cents a share. However, this still covers the consensus estimate. Shares were losing $1.73 to $4.60. Enzon Pharmaceuticals ( ENZN) jumped on news that it had submitted an application to the Food and Drug Administration for the development of an antagonist drug that targets multiple cancer processes, including solid tumors, called HIF-1 alpha. The Bridgewater, N.J., company licensed the drug from Denmark-based Santaris Pharma in July 2006. Shares were rising 59 cents, or 7%, to $9. Learning Tree ( LTRE), which develops classroom courses for Internet technology professionals, gained on word of an expected rise in fiscal fourth-quarter results, as well as an earnings restatement that will probably fall in line with previously announced estimates to that effect. Profits from operations are projected at $200,000, which compares with a restated year-ago loss of $800,000, and revenue should rise 6% to $37.7 million. The analyst who follows the company is looking for $38.6 million.