diff --git a/src/sindi/comparator.py b/src/sindi/comparator.py
index ce4ed11..c98e528 100644
--- a/src/sindi/comparator.py
+++ b/src/sindi/comparator.py
@@ -7,6 +7,7 @@
 from src.sindi.rewriter import Rewriter
 from src.sindi.utils import printer
 import z3
+import re
 
 
 class Comparator:
@@ -51,16 +52,7 @@ def compare(self, predicate1: str, predicate2: str) -> str:
         # Convert ASTs to SymPy expressions
         expr1 = self._to_sympy_expr(ast1)
         expr2 = self._to_sympy_expr(ast2)
-
-
-        printer('*' * 140)
-        printer('*' * 140)
-        printer(f"expr1 this time is: {self.simplifier._to_sympy(ast1)}")
-        printer(f"expr2 this time is: {self.simplifier._to_sympy(ast2)}")
-        printer('*' * 140)
-        printer('*' * 140)
-
-        
+     
         printer(f'> expr1: {expr1}')
         printer(f'> expr2: {expr2}')
 
@@ -134,6 +126,19 @@ def _is_strict_vs_neq_same_operands(self, a, b):
         return False
 
     def _to_sympy_expr(self, ast):
+        def _sanitize_sym_name(s: str) -> str:
+            # keep alnum/underscore; collapse others to single '_'
+            s = re.sub(r"[^A-Za-z0-9_]", "_", str(s))
+            s = re.sub(r"_+", "_", s).strip("_")
+            return s or "sym"
+
+        def _symbol_from_call(func_name: str, arg_exprs):
+            # include args in the symbol name for disambiguation
+            parts = [_sanitize_sym_name(func_name)]
+            if arg_exprs:
+                parts.extend(_sanitize_sym_name(a) for a in arg_exprs)
+            return sp.Symbol("__".join(parts))
+
         if not ast.children:
             try:
                 return sp.Number(float(ast.value)) if '.' in ast.value else sp.Number(int(ast.value))
@@ -145,20 +150,19 @@ def _to_sympy_expr(self, ast):
                     return sp.false
                 return sp.Symbol(ast.value.replace('.', '_'))
 
-        # Handle indexed attributes: a[b].c
+        
+        # Handle indexed attributes: a[b].c  -> symbolic atom with args baked in
         if '[]' in ast.value and '.' in ast.value:
-            # Create a single function name from the complex expression
-            # e.g., "coinMap[].coinContract.balanceOf()" becomes a function call
             func_name = ast.value.replace('[]', '').replace('()', '').replace('.', '_')
             args = [self._to_sympy_expr(child) for child in ast.children]
-            return sp.Function(func_name)(*args)
+            return _symbol_from_call(func_name, args)
 
         # Handle indexing without attributes: a[b]
         if '[]' in ast.value:
             base_name = ast.value.replace('[]', '')
             base = sp.IndexedBase(base_name)
             index = self._to_sympy_expr(ast.children[0])
-            return base[index]
+            return _symbol_from_call(base_name, [index])
 
         args = [self._to_sympy_expr(child) for child in ast.children]
         
@@ -198,8 +202,9 @@ def _to_sympy_expr(self, ast):
         elif ast.value == '*':
             return sp.Mul(*args)
         elif '()' in ast.value:
-            func_name = ast.value.replace('()', '')
-            return sp.Function(func_name)(*args)
+            # Treat calls as Boolean/unknown atoms so And/Or/Not accept them
+            func_name = ast.value.replace('()', '').replace('.', '_')
+            return _symbol_from_call(func_name, args)
 
         return sp.Symbol(ast.value.replace('.', '_'))
 
diff --git a/src/sindi/rewriter.py b/src/sindi/rewriter.py
index 6d4d98c..064067e 100644
--- a/src/sindi/rewriter.py
+++ b/src/sindi/rewriter.py
@@ -56,10 +56,10 @@ class Rewriter:
 
     _ETH_MULT = {"ether": 10**18, "gwei": 10**9, "wei": 1}
 
-    # ---------------- NEW: parenthesized assignment and finalization mask ----------------
+    # ---------------- Parenthesized assignment and finalization mask ----------------
     # Replace occurrences of '(var = expr)' with 'expr' (single '=' only).
     _PAREN_ASSIGN = re.compile(
-        r"\(\s*([A-Za-z_]\w*)\s*=\s*(.*?)\s*\)"
+        r"\(\s*([A-Za-z_]\w*)\s*=\s*(?![=])(.*?)\s*\)"
     )
 
     # (X & MarketplaceLib.FLAG_MASK_FINALIZED) == 0  -->  !MarketplaceLib.isFinalized(X)
diff --git a/tests/comparator_test_set.json b/tests/comparator_test_set.json
index d3ba558..0c16739 100644
--- a/tests/comparator_test_set.json
+++ b/tests/comparator_test_set.json
@@ -57,7 +57,8 @@
             ["fee == 10**18 wei", "fee == 1000000000000000000"],
             ["x == 1e18 wei", "x == 1000000000000000000"],
             ["to != 0x0000000000000000000000000000000000000000", "to != address(0)"],
-            ["x == 0x80ac58cd", "x == type(IERC721).interfaceId"]
+            ["x == 0x80ac58cd", "x == type(IERC721).interfaceId"],
+            ["_msgSender() == owner || isApprovedForAll(owner, _msgSender())", "_msgSender() == owner || isApprovedForAll(owner, _msgSender())"]
         ],
         "The predicates are not equivalent and neither is stronger.": [
             ["a > 0", "a < 0"],