Merge multiple files based on name and different indicator

[k_a_r_o_l]

Hello,

How to merge multiple files in one catalog. Two files with the same name but different indicator S1/S2 should give one file.

Example:
600sbD_S1_R1_001.fastq
600sbD_S2_R1_001.fastq
550sbD_S1_R1_001.fastq
550sbD_S2_R1_001.fastq
537sbD_S1_R1_001.fastq
537sbD_S2_R1_001.fastq


Files S1 and S2 starting the same should be merged giving an output:
600sbD.fastq
550sbD.fastq
537sbD.fastq