Yes you can use it, it will simply be another sewer stack in your house, but you need to leave a cleanout there that is the same size, just pipe it the same way as the other stack in your house, only you will use 1-1/2" pipe for the stack instead of 3". It will still need a TY taken off the stack, a p-trap for the sink and a vent off the top of the TY that will be connected into the venting system above the flood level of the highest fixture on the system drain. The only reason you have a cleanout there is code states that your main stack, which looks to be the one under you bathroom, must be within 5' of the wall where the sewer enters you house, if it is more than 5', you require a main cleanout like the one you want to use as a drain. You may have some difficulty connecting to this pipe as it is old school lead and oakum and the hub of the pipe is just showing at concrete level. You must either caulk a new adapter into the hub(after the removal of the cleanout) or chip up the concrete and cut the cast below the bell of the cast iron, not a whole lot of option that I know of if you want to stay in code.