Kudos to Charlie who noted the solution could not have 10 digits or it wouldn't be a prime (sod=45).  Silly me, my program ran for hours getting from 10 digits down to 9, but ultimately found the same answer as the others:   987,654,103.

(re-written to start from 9 digits):

def isprime(n):
    '''check if integer n is a prime'''
    n = abs(int(n))
    if n < 2:
        return False
    if n == 2:
        return True    
    if not n & 1:
        return False
    for x in range(3, int(n**0.5)+1, 2):
        if n % x == 0:
            return False
    return True

for n in range(987654321,1,-2):
    s = str(n)
    if len(s) > len(set(s)):
        continue
    if isprime(n):
        print(n)
        break