Stacking multiple columns into one with duplication of other columns

Hi, I have a problem which I have tried to solve for some time but without success. Any help would be greatly appreciated!

Basically, my problem is that I have several columns which should be merged into one. An example
Row Column A Column B Column C Column D Column E
1 wa wc 4 2
2 wa 3 4
3 wc wb wa 1 5

In this example I want 6 rows. The first row should contain column A, D and E (with the column values of wa, 4, 2), second row column B (i.e. wc, 4,2) third row column A again (i.e. wa,3,4) fourth row column A (i.e. wc,1,5), fifth row column B (i.e. wb,1,5) sixth row column C (i.e. wa,1,5).

I have attached a example of before/after transformation!