MOST NOTEWORTHY: Walgreen, CBS Corp, SL Green Realty, Brandywine Realty Trust and Navteq were today's noteworthy downgrades:

• Walgreen (NYSE: WAG) was downgraded to Neutral from Buy at Merrill and to Market Perform from Outperform following its weak Q4 report. Merrill sees limited upside following the worse-than-expected quarter.
  
• CBS Corporation (NYSE: CBS) was downgraded to Hold from Buy at Deutsche Bank to reflect the company's soft rating trends and poor local advertising growth.
  
• Banc of America downgraded shares of SL Green Realty (NYSE: SLG) and Brandywine Realty Trust (NYSE: BDN) to Neutral from Buy. The firm downgraded shares of SL Green to reflect their more cautious stance on the office sector and believes uncertainty over cap rates will limit share upside, and downgraded shares of Brandywine to reflect a lack of near-term catalysts and their more cautious stance on the office sector.
  
• Navteq Corporation (NYSE: NVT) was downgraded to Neutral from Buy at UBS and to Market Perform from Outperform at JMP Securities following its acquisition by Nokia Corporation (NYSE: NOK).

OTHER DOWNGRADES:

• Goldman Sachs removed Monsanto Company (NYSE: MON) from its Conviction Buy List.
  
• The firm downgraded Air Products & Chemicals (NYSE: APD) to Neutral from Buy and Valspar Corporation (NYSE: VAL) to Sell from Neutral.
  
• CIBC downgraded Axcan Pharma (NASDAQ: AXCA) to Sector Performer from Sector Outperformer.
  
• Humana Inc (NYSE: HUM) was downgraded to Neutral from Buy at Merrill.

For some companies, focusing on a single specialization is the best way to build a reputation, leverage resources and maximize effectiveness. There is a Mont-Saint-Hilaire, Quebec outfit that has followed that path to leadership in the field of gastroenterology-related pharmaceuticals.

Axcan Pharma (NASDAQ: AXCA) is engaged in the development and sale of pharmaceutical products for the treatment of gastrointestinal diseases and disorders. Products include medicines for exocrine pancreatic insufficiency diseases; cholestatic liver diseases; inflammatory bowel diseases; gastric duodenal ulcers; and irritable bowel syndrome. The firm also owns the global rights to Photofrin, a drug with applications to esophageal, gastric and lung cancers. Other products include caloric supplements for cystic fibrosis patients and over-the-counter antacids. The company sells its products primarily to wholesale drug companies and distributors. Novartis (NYSE: NVS) is a major competitor.

The firm pleased investors last week, when it reported fiscal Q3 EPS of 36 cents and revenues of $92.3 million. Analysts had been expecting 26 cents and $81.6 million. Management also guided FY07 revenues to $335-$343 million, versus Street consensus of $324.74 million.