Noman, I don't know your discipline or research context or topic. But in general, I don't see why not. There is nothing fundamentally methodologically wrong about writing an article based on a single case study. However, multiple cases always tell a more nuanced story regardless of discipline. In that context, if you want to use a single case in an article, you should also think about telling the reader WHY you chose that particular case for the purpose of that article. For example, does it represent a rare circumstance? is it an exemplar of the phenomenon you are trying to study? etc. I would consult Yin 1994 Sage book on Case Study Research and articles by Kathleen Eisenhardt and Siggelkow 2007 article in Academy of Management Journal.