Anatoly Nikolayevich Alexandrov(1888-1982) was a Russian composer-pianist-educator. Being a pupil of Sergei Taneyev, on the line of Rachmaninov and Metdner, he wrote 14 piano sonatas, 4 operas, 2 symphonies and many pieces for piano in his long life.
His works in the 1920s are remarkable. They are more tonal than other radical Russian avand-gurdist, but there is still abandance of poetic and fantasic musical atmosphere. As same as other Soviet composers, his style was no more radical and classical after Statin's dictatorship in 1930s. Until his death, he wrote rather classical works. Personally, I recommend his Piano Concerto in Tchaikovsky-Rachmaninovian manner in 1972 (https://www.youtube.com/watch?v=dYkzU... the final movement)
His Piano Sonata No.5 was composed in 1922-23. The composer himself describes it as "Powerful roll(Kren) in the foreign country". The second theme in the 1st movement has pentatonic scales, which makes opus exotic and orientalistic. It may be a proof that he was somehow interested in the music of Russian people and East. He himself studied and transcribed folk-tunes in Bashkir for piano, and moreover in the later days his pupils include figures who was major in the Central Asia (Khalmamedov, Mushel and Kara Karaev).
1st mov. (Quasi andantino sempre molto flessibile)
The classical sonata form in G# minor. 1st theme is a slow, dreaming and floating tune in triplets. 2nd theme appears in PP. It sound like divine choral. Then various elaborate subjects lead to the climax in C minor in FFF. After rather short recaptulation coda is played mostly in 16th notes. It ends quietly.
It consists of theme and 10 variations (including Coda). Base tonality is A-flat major.
Theme (7:35) Tranquillo
A single tune with irregular beats, appearently influenced by Russian folklore. the construction is 7 bars (monophony) + 7 bars (homophony in the low voice).
Var.1(8:18) L'istesso tempo
The first half of theme is played on the left hand, while the right hand plays duzzling ornaments in the high voice.
Var.2 (9:09) Piu mosso, gaio
Theme is played in accords in the both hands.
Var.3 (9:44) Veloce
A major. While the right hand plays fast passage in quintuplet,
the left hand jumps around the beginning of beat. In the latter part, passage in unison appears.
Var.4 (10:17) Non troppo lento, misterioso
D sharp minor. A slow, dark and poetic variation.
Var.5 (11:44) Piu mosso, molto risoluto
B minor but it ends in F minor. Free and decisive variation on the waltz-like rhythm after a short introduction in lento.
Var.6 (12:13) L'istesso tempo, ma piu flessibile ed un poco agitato
F minor. the right hand plays theme and 8th notes in flexible tempo. The latter part has strong trills.
Var.7 (12:57) A tempo(l'istesso tempo) giocoso
Fast and light perpetuum mobile in sixteenth notes.
Var.8 (13:10) Lo stesso tempo
It begins with attaca from the former variation, but the tonality is effectively changed into E major. After descending passage played by both hands, with the short slow motif "con importance", led to Fugue.
Var.9 (13:44) Fuga - Tempo giusto
Atonal fugue in the four-voice described by the composer as "kanon deliberately done in fifth". After that 2nd theme of the 1st movement is played in FFF in the same tempo with the return of solid tonality A flat minor.
Var.10(17:11) Coda : Meno mosso tranquillo
A flat major. Theme is played in half tempo. The sonata ends quietly.
This sonata was peformed by the composer in 1924 at Moscow, and then the dedicatee Samuel Feinberg played once. However after that it seems that no one peformed. It seems that there is no recording until this video possibly because the construction is not so well as his more major works like Sonata No.4 and musical language and score-writing are too complex. For example, In the 1st movement, there are plenty of double sharp and it makes the score very confusing (in the revised version, it was improved). Even the composer himself regards it as "insufficiently complex".