Here are some thoughts. You can sometimes apply the rule of 12 and the nitrogen rule to good effect. Try subtracting the mass of a fragment from M. More specifically, your spectrum has an unusual feature. I am only familiar with two functional groups that often display this feature (there might be others). Identifying likely functional groups might cut the territory down.
Hi Babcock !!
Usually the -1 loss with an high peak is an aldehyde...
But I also see a -18 loss (water) that I think is typical of alcahol and carboxylic acid (perhaps COOH gives -17 not 18)....I also see a -28 loss so there sould be a C=O!
Also I see a 76 instad a 77...can it mean that the ring has two substituents? maybe an aldehyde and an alcohol??
PS: I also see that when I loss the aldehydic group (29) I get 93, that should be phenyl + alcohol.
PS: what do you mean with nitrogen rule? That if M+* is even I don't have nitroger or at least 2N/4N ecc ??