import re 

pattern_aptnum = re.compile(r'^\d+|\bNo\s*\d+')
pattern_street = re.compile(r'^\d+,?\s*(.*)|^(.*?)\s+No\s*\d+') 
for i in ["32 Syndicate street","Street 45 No 100","15, Tom and Jerry Street"]:
    fin_street = ""
    fin_aptnum = ""
    print("String:", i)
    match_street = pattern_street.search(i)
    if match_street:
        fin_street = match_street.group(1) or match_street.group(2)
    match_aptnum = pattern_aptnum.search(i)
    if match_aptnum:
        fin_aptnum = match_aptnum.group()

    print("street--",fin_street)
    print("apartmentnumber--",fin_aptnum)