Here is a solution for your problem using the string split and index of,
import java.util.ArrayList;
public class StringSplit {
public static void main(String[] args) {
String[] seperatedStr = null;
int fourthStrIndex = 0;
String modifiedStr = null, finalStr = null;
ArrayList<String> strList = new ArrayList<String>();
strList.add("31451 CID005319044 15939353 C8H14O3S2 beta-lipoic acid C1C[S@](=O)S[C@@H]1CCCCC(=O)O ");
strList.add("12232 COD05374044 23439353 C924O3S2 saponin CCCC(=O)O ");
strList.add("9048 CTD042032 23241 C3HO4O3S2 Berberine [C@@H]1CCCCC(=O)O ");
for (String item: strList) {
seperatedStr = item.split("\\s+");
fourthStrIndex = item.indexOf(seperatedStr[3]) + seperatedStr[3].length();
modifiedStr = item.substring(fourthStrIndex, item.length());
finalStr = modifiedStr.substring(0, modifiedStr.indexOf(seperatedStr[seperatedStr.length - 1]));
System.out.println(finalStr.trim());
}
}
}
Output:
beta-lipoic acid
saponin
Berberine