Michael Gilbert 
Dust and The Heat [PDF ebook] 

Oliver Nugent is a young Armoured Corps officer in the year 1945. Taking on a near derelict pharmaceutical firm, he determines to rebuild it and make it a success. He encounters some ruthless opposition, and counteracts with some fairly unscrupulous methods of his own. It seems no one is above blackmail and all is deemed fair in big business battles. Then a threat: apparently from German sources it alludes to a time when Oliver was in charge of an SS camp, jeopardizing his company and all that he has worked for.