C# compre two classes structure

How to compare and get differences between two classes.

public class Class1{

public string S1{get;set;}
public string S2{get;set;}
public Class2 C3{get;set;}
}

public class Class2{

public string S1{get;set;}
public string S2{get;set;} 
}

public class Class3{

public string S1{get;set;}
public string S2{get;set;}
public string S12{get;set;}
public Class4 C3{get;set;}
}

public class Class4{

public string S1{get;set;}
public string S2{get;set;}
public string S112{get;set;} 
}

At the end I want to know that there is missing member witout creating instances of classes

public string S112{get;set;}   

and

public string S12{get;set;}