using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?im)^(?:[^a-z].*\r?\n)*([a-z]+).*(\r?\n[^a-z].*)*";
string substitution = @"$1";
string input = @"(IUPAC: Disilver sulfide)
Acanthite (Y: 1855) 02.BA.35 [18] [19] [20]
(IUPAC: Disilver sulfide)
Acetamide (1974-039) 10.AA.20 [21] [22] [23]
(IUPAC: Acetic acid amide)
Achalaite (2013-103) 04.?? [24] [no] [no]
Achavalite (Y: 1939";
Regex regex = new Regex(pattern);
string result = regex.Replace(input, substitution);
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx