I think the notes are B, A, G, E, D. Just try to play like glissando but don't forget to go 2 (played) notes back. I mean sth like: B4...A4-G4-E4-A4-G4-E4-D4-B3-E4-D4-B3-A3-G3-B3-A3-G3-E3-D3-G3-E3-D3-B2-A2-D3..... Something like playing 5 notes 'down' (except at the beginning, as you can see) and going back 2 notes 'up' to play 5 notes 'down' and so on. This way you'll get two next notes before you 'go back', so you should finally get the G1 note. Stop here and then play a few notes 'up'. It sounds complicated, but you must count on your intuition. Playing it as fast as in the original might be difficult. If you go back to early or too late, don't worry - I think it will still sound good

Mike