Panmure Gordon has retained its 'buy' rating and 2,900p target price cigarette and tobacco group Imperial Tobacco but has raised some concerns after the company noted challenging conditions in some markets in the first quarter."We remain attracted to Imperial on its valuation; however in order for the discount to its peers to narrow we believe that delivery of its organic strategy needs to accelerate."Media and advertising giant WPP was performing well on Wednesday morning after Jefferies upgraded its rating for the stock from 'hold' to 'buy'.The broker said that an analysis WPP's largest clients and their 2013 ad budgets "looks encouraging" and "with expectations low, we see upside risk".Seymour Pierce has reiterated its 'buy' rating for iron ore producer Ferrexpo despite the company revealing a sharp drop in earnings."Although we will be re-examining our estimates in light of this release this morning we reiterate our positive stance on Ferrexpo. Indeed, we believe there are a number of catalysts around the corner that will have a positive effect on the share price over the next few quarters," said analyst Matthew McDonald.BC