Figure 5-3 Ribose can be synthesized from formalheyde in abiotic conditions

5-4 Formaldehyde and hydrogen cyanide can lead to the synthesis of various amino acids, in this case of glycine.

RNAs (adenine, guanine, cytosine, and uracil) have all been obtained in abiotic conditions, but thymine has never been found, which means that primitive nucleic acids could have been RNAs but not DNAs.
Even if the atmosphere of the primitive Earth could change within ample limits, therefore, we are bound to conclude that the first oceans became rapidly filled with a high number of organic molecules.