What is the compound B for the following reaction?

13.png What is 1 pointing to?

10.png What is 2 pointing to?

1.png What is 1 pointing at?

16.png What is 1 pointing at?

10.png What is 4 pointing at?

9.png What is 2 pointing to?

1.png What is 3 pointing to?

2.png What is 4 pointing to?

15.png What is 2 pointing at?