JPPR2
Time for me to learn some more if possible as I have some of these trees here and I haven't a clue what they are.
I asked the Missus but she doesn't know in English but she said she calls them "sour leaf tree", I presume that's her interpretation of the Thai name.
What I can tell you is they get eaten alive, the MIL sells the leaves as fast as they can grow. Picking them promotes better growing.
Here's a young one
And an older one which has been hacked to get it to grow more leaves.
You can see it here next to the Jackfruit tree. This area is at the bottom of the outside kitchen which is at the back (west side) of our house
Cheers