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3alpha-hydroxy-5alpha-pregnan-20-one

362,296 routes · scope human · up to 3 steps · built 5 October 2026 · Reactions · API

Inferred

Every route here is a hypothesis drawn from reference reactions (Rhea and Human-GEM), not a finding. Currency species such as water, ATP and NAD(H) never form a step. Evidence key

12 compounds within 3 steps: 1 in 1, 2 in 2, 9 in 3

Does it reach a compound?

One step

5alpha-pregnane-3,20-dioneReach from here →
1. 3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1cytosolOne of 3 routes

Two steps

progesteroneReach from here →
1. 3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
2. 5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 3 morecytosol
20alpha-hydroxy-5alpha-pregnane-3-oneReach from here →
1. 3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
2. 5alpha-pregnane-3,20-dione + NADPH + H(+) = 20alpha-hydroxy-5alpha-pregnane-3-one + NADP(+)
Catalysed by AKR1C4, AKR1C3, AKR1C2

Three steps

16alpha-hydroxyprogesteroneReach from here →
Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 5 morecytosol
21-hydroxyprogesteroneReach from here →

cytosol

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 4 morecytosolOne of 3 routes

17alpha-hydroxyprogesteroneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
cytochrome P450 (progesterone)

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 4 morecytosolOne of 3 routes

11beta-hydroxyprogesteroneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
progesterone,reduced ferredoxin:oxygen oxidoreductase (11-hydroxylating)

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 5 morecytosolOne of 2 routes

(20S)-hydroxypregn-4-en-3-oneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
(20S)-hydroxypregn-4-en-3-one + NAD(+) = progesterone + NADH + H(+)

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 4 morecytosolOne of 2 routes

5beta-pregnan-3,20-dioneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
progesterone + NADPH + H(+) = 5beta-pregnan-3,20-dione + NADP(+)

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 4 morecytosol

(20R)-20-hydroxypregn-4-en-3-oneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
20alpha-Hydroxy-4-pregnen-3-one:NADP+ 20-oxidoreductase

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 3 morecytosol

6beta-hydroxyprogesteroneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
progesterone + reduced [NADPH--hemoprotein reductase] + O2 = 6beta-hydroxyprogesterone + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 6 morecytosol

3beta-hydroxypregn-4-ene-20-oneReach from here →

3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
progesterone + NADPH + H(+) = 3beta-hydroxypregn-4-ene-20-one + NADP(+)

Catalysed by AKR1C4, AKR1C3, AKR1C2, AKR1C1 and 4 morecytosol