Stop calling them life’s building blocks. You cannot construct life using just that. Compounds found in living creatures, and in rocks.
My erudite coworkers 30 years ago more or less blew me off when I brought up the question of “handedness” in amino acids and sugars. They still haven’t a clue how it could happen.
Miracle #1: Amino acids link up into polymers at least 200 units long.
Miracle #2: All the amino acids are left-handed.
Miracle #3-???