I've been reading a lot of scale e-books from the best authors including Dave Celentano, Adam Kadmon, Al Politano, Howard Wallach, Rich Cochrane, J.P. Befumo, or articles from Wikipedia and the Internet but this scale structure was never formally listed or given much attention as far as I know so I decided to share it here on UG.
The scale formula is 1-2-3-4-5-b6-b7-7.
With C as the root, the spelling would be C-D-E-F-G-Ab-Bb-B-C and the closest diatonic key signature - in terms of it's sound (not statistical comparison), would probably be C major.
Here's a list of the triads and sevenths that could be built from the scale notes:
C, C7, Cmaj7, Caug, Cmaj7#5
Fm, FmM7, Fdim, F°7
G, G7, Gm, Gm7
Dm7b5, D°7, Ddim
E, E7, Eaug, Edim, Em, Em7, Em7b5
Abaug, AbM7#5, Abdim, Ab°7
Try blending the scale with the chords above to see what happens.
Just for the record, the scale could be quickly analyzed as the 6th mode of an F melodic minor scale with an additional flatted 5th (starting from F), or a C Indian Sarasangi scale with an added flatted 7th (starting from C). The added b7th note (Bb) gives it an extra quality.