...a mixture of short-chain organic molecules produced by photolytic chemistry. That being said it's not really thought to be what life came from - rather it shows the small molecules that compose life's much larger molecules can be made via inorganic processes. No one says life sprang from tholins, just that the synthesis of tholins mean the construction materials of life were readily available when the process - whatever it was - began.

Between a heterochiral mixture of amino acids and pieces of nucleotides, to a viable molecular ecosystem of self-replicating RNAs is a VERY big gap in current scenarios of life's origins, and as yet no theoretical account of the journey from tholins to replicators has universal agreement. That doesn't mean the task is impossible nor does it mean it's a sure thing for human inquiry, just that it's a big frontier that's yet to be explored in much detail. As super-computers simulate bigger and bigger molecules, thus intelligently guiding our explorations of organic chemistry, we might find all sorts of incredible steps - and possible alternative pathways - between amino acids and replicators. Whole new substrata of large molecule life might become obvious - alternatives to DNA-RNA and so forth, so for many reasons the quest is worthwhile.