Aleph-1 (DoT) shulgins favorite chemical

So I see almost no information on this chemical other than shulgins love for it and so I have a few questions. If it's so amazing why isn't more popular? Obviously LSD had a massive marketing advantage but still it should've showed up eventually right? Also I don't understand the laws or chemistry but is this stuff legal? If so why is it impossible find and if it is illegal is it available on DNMs? I'll check when I can I'm at work right now.

Also any experiences or information anyone has would be awesome to hear about.

EDIT: is it actually illegal? (In US mainly but everywhere)