Aligned Pent Exclusion

The cells A4, B4, C4, D6 and E6 can together accept various combinations of values. But some combinations of values can be excluded, because they would leave some cells with no potential values.

More precisely, the following combinations of values are not possible for the cells A4, B4, C4, D6 and E6:
2, 8, 4, 4 and 3 because the cell A6 must contain 2 or 3
2, 8, 4, 4 and 9 because the cell B6 must contain 8 or 9
2, 8, 4, 8 and 3 because the cell A6 must contain 2 or 3
2, 8, 4, 8 and 9 because the cell B6 must contain 8 or 9
2, 8, 4, 9 and 3 because the cell A6 must contain 2 or 3
2, 8, 7, 4 and 3 because the cell A6 must contain 2 or 3
2, 8, 7, 4 and 9 because the cell B6 must contain 8 or 9
2, 8, 7, 8 and 3 because the cell A6 must contain 2 or 3
2, 8, 7, 8 and 9 because the cell B6 must contain 8 or 9
2, 8, 7, 9 and 3 because the cell A6 must contain 2 or 3
8, 8, 0, 0 and 0 because the value can occur only once in the region
9, 8, 2, 4 and 3 because the cell A6 must contain 2 or 3
9, 8, 2, 4 and 9 because the cell B6 must contain 8 or 9
9, 8, 2, 8 and 3 because the cell A6 must contain 2 or 3
9, 8, 2, 8 and 9 because the cell B6 must contain 8 or 9
9, 8, 2, 9 and 3 because the cell A6 must contain 2 or 3
9, 8, 4, 4 and 3 because the cell B6 must contain 8 or 9
9, 8, 4, 4 and 9 because the cell B6 must contain 8 or 9
9, 8, 4, 8 and 3 because the cell B6 must contain 8 or 9
9, 8, 4, 8 and 9 because the cell B6 must contain 8 or 9
9, 8, 4, 9 and 3 because the cell B6 must contain 8 or 9
9, 8, 7, 4 and 3 because the cell B6 must contain 8 or 9
9, 8, 7, 4 and 9 because the cell B6 must contain 8 or 9
9, 8, 7, 8 and 3 because the cell B6 must contain 8 or 9
9, 8, 7, 8 and 9 because the cell B6 must contain 8 or 9
9, 8, 7, 9 and 3 because the cell B6 must contain 8 or 9

Because some potential values of B4 occur in none of the remaining combinations, they can safely be removed.