Rename files from a txt list

I'm trying to develop a small program that allows me to rename a set of files (type pdf in a given directory and whose name is sequential: 001.pdf, 002.pdf, 003.pdf, etc.), using existing information in a txt file.

The information in the txt file is of the following genre:

  

"2500" "_" "W1" "001" "E" "04"

     

"2500" "_" "W1" "002" "E" "05"

     

"2500" "_" "W1" "003" "E" "04"

The goal is for pdf files to be renamed based on the text lines of the txt, not using the quotation marks. For example the file 001.pdf would be 2500_W1001E04.pdf and so on.

The code that I already have and that I think may allow you to go further is the following:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;

namespace _utilitarios
{
    public partial class FormRenomear : Form
    {
        public FormRenomear()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //Diretorio que contem os ficheiros pdf e o txt de referência para a renomeação dos ficheiros.
            string directory = @"C:\Users\arquivo1\arquivo2\";

            //Ficheiro do tipo txt que contém a lista para renomear os ficheiros.
            string filenames = File.ReadAllText(directory + "lista.txt");

            //Remove as aspas e separa por espaços.
            string[] listFilenames = filenames.Replace("\"", "").Split('\t');

            int i = 0; //Usado para aceder á lista de ficheiros.
            foreach (string file in Directory.GetFiles(directory))
            {
                //Ignorar o ficheiro txt.
                if (!file.EndsWith(".txt"))
                {
                    //Renomear o ficheiro.
                    File.Move(file, directory + listFilenames[i] + ".pdf");
                    i++;
                }
            }
        }
    }
}