That’s a part of the vector:

c("tr|A0A075F5C6|A0A075F5C64_MORGAN", "sp|AC087WPF7|AUTS2_MORGAN", 
  "tr|A0A087WPU4|CCC087WPU4_MORGAN", "tr|DAA08W8RK1|A0A087WRK1_MORGAN", 
  "tr|A0A087WRT4|AFW0987WRT4_MORGAN", "tr|A0A087WSP5|A0A087WSP5_MORGAN"
)

The part which I am interested in is between | , for example first one is: A0A075F5C6. I was trying with regex but can not target it… Can you help me with a code which will allow me to extract only these strings from the character vector…