words <- c("somethingspan.", "..span?", "spanthank", "great to hear", "yourspan")
words <- gsub("[[:punct:]]*span[[:punct:]]*", "", words)
words <- words[words != ""]
paste(words, collapse=" ")
d29yZHMgPC0gYygic29tZXRoaW5nc3Bhbi4iLCAiLi5zcGFuPyIsICJzcGFudGhhbmsiLCAiZ3JlYXQgdG8gaGVhciIsICJ5b3Vyc3BhbiIpCndvcmRzIDwtIGdzdWIoIltbOnB1bmN0Ol1dKnNwYW5bWzpwdW5jdDpdXSoiLCAiIiwgd29yZHMpCndvcmRzIDwtIHdvcmRzW3dvcmRzICE9ICIiXQpwYXN0ZSh3b3JkcywgY29sbGFwc2U9IiAiKQo=