getting string from string start wtih "abc" and end with "def"

I am using StringUtils (import org.apache.commons.lang3.StringUtils;) library to split string like:

String str = "15684zxcvVariableCanChancedefABCDEND";

I need to take out string start with zxcv* and end with *def as

String tmp = zxcvVariableCanChancedef;

any help?