In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

['495', 'd', 'r', 'v', 'n', 'v', '8133', '837', 'b', '4495', 'k', 'x', '1735', 'h', '1579', 'd', 'v', 'f', '2375', '3297', '7607', '4859', 'k', '9661', 'v', 'd', '1309', 'q']
b, d, f, h, k, n, q, r, v, x