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pregn-5-ene-3,20-dione

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

21 compounds within 3 steps: 1 in 1, 10 in 2, 10 in 3

Does it reach a compound?

One step

progesteroneReach from here →
1. steroid Delta-isomerase (pregn-5-ene-3,20-dione)
Catalysed by HSD3B1, HSD3B2cytosolOne of 2 routes

Two steps

16alpha-hydroxyprogesteroneReach from here →
1. steroid Delta-isomerase (pregn-5-ene-3,20-dione)
2. progesterone + reduced [NADPH--hemoprotein reductase] + O2 = 16alpha-hydroxyprogesterone + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)
Catalysed by HSD3B1, HSD3B2, CYP3A4, CYP1B1cytosol
21-hydroxyprogesteroneReach from here →
1. steroid Delta-isomerase (pregn-5-ene-3,20-dione)
2. cytochrome P450 (progesterone)
Catalysed by HSD3B1, HSD3B2, CYP21A2cytosolOne of 3 routes

Three steps

acetaldehydeReach from here →
Catalysed by HSD3B1, HSD3B2, CYP17A1cytosol, endoplasmic reticulum
(17R,20S)-17,20-dihydroxypregn-4-en-3-oneReach from here →
Catalysed by

17alpha-hydroxyprogesterone

Reach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
cytochrome P450 (progesterone)

Catalysed by HSD3B1, HSD3B2, CYP17A1cytosolOne of 3 routes

11beta-hydroxyprogesteroneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
progesterone,reduced ferredoxin:oxygen oxidoreductase (11-hydroxylating)

Catalysed by HSD3B1, HSD3B2, CYP11B1, CYP11B2cytosolOne of 2 routes

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

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
(20S)-hydroxypregn-4-en-3-one + NAD(+) = progesterone + NADH + H(+)

Catalysed by HSD3B1, HSD3B2, AKR1C4, HSD17B2 and 3 morecytosolOne of 2 routes

5alpha-pregnane-3,20-dioneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase

Catalysed by HSD3B1, HSD3B2, SRD5A1, SRD5A2 and 1 morecytosolOne of 2 routes

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

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
progesterone + NADPH + H(+) = 5beta-pregnan-3,20-dione + NADP(+)

Catalysed by HSD3B1, HSD3B2, AKR1D1cytosol

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

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
20alpha-Hydroxy-4-pregnen-3-one:NADP+ 20-oxidoreductase

Catalysed by HSD3B1, HSD3B2, AKR1C1cytosol

6beta-hydroxyprogesteroneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
progesterone + reduced [NADPH--hemoprotein reductase] + O2 = 6beta-hydroxyprogesterone + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)

Catalysed by HSD3B1, HSD3B2, CYP3A4, CYP3A5 and 1 morecytosol

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

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
progesterone + NADPH + H(+) = 3beta-hydroxypregn-4-ene-20-one + NADP(+)

Catalysed by HSD3B1, HSD3B2, HSD17B7cytosol

cytosol

One of 2 routes

androst-4-ene-3,17-dioneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
cytochrome P450 (progesterone)
cytochrome P450 (17alpha-hydroxyprogesterone)

Catalysed by HSD3B1, HSD3B2, CYP17A1cytosolOne of 5 routes

corticosteroneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
progesterone,reduced ferredoxin:oxygen oxidoreductase (11-hydroxylating)
cytochrome P450

Catalysed by HSD3B1, HSD3B2, CYP11B1, CYP11B2 and 1 morecytosolOne of 4 routes

aldosteroneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
cytochrome P450 (progesterone)
cytochrome P450 (11-deoxycorticosterone)

Catalysed by HSD3B1, HSD3B2, CYP21A2, CYP11B2cytosol, mitochondrial matrix

11-deoxycortisolReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
cytochrome P450 (progesterone)
cytochrome P450 (17alpha-hydroxyprogesterone)

Catalysed by HSD3B1, HSD3B2, CYP17A1, CYP21A2cytosolOne of 3 routes

acetateReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
cytochrome P450 (progesterone)
cytochrome P450 (17alpha-hydroxyprogesterone)

Catalysed by HSD3B1, HSD3B2, CYP17A1cytosolOne of 4 routes

3alpha-hydroxy-5alpha-pregnan-20-oneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
3alpha-hydroxy-5alpha-pregnan-20-one:NADP+ 3-oxidoreductase (A-specific)

Catalysed by HSD3B1, HSD3B2, SRD5A1, SRD5A2 and 5 morecytosolOne of 3 routes

16alpha,17alpha-dihydroxyprogesteroneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
cytochrome P450 (progesterone)
17alpha-hydroxyprogesterone + reduced [NADPH--hemoprotein reductase] + O2 = 16alpha,17alpha-dihydroxyprogesterone + oxidized [NADPH--hemoprotein reductase] + H2O + H(+)

Catalysed by HSD3B1, HSD3B2, CYP17A1cytosol

20alpha-hydroxy-5alpha-pregnane-3-oneReach from here →

steroid Delta-isomerase (pregn-5-ene-3,20-dione)
5alpha-pregnane-3,20-dione:NADP+ delta4-oxidoreductase
5alpha-pregnane-3,20-dione + NADPH + H(+) = 20alpha-hydroxy-5alpha-pregnane-3-one + NADP(+)

Catalysed by HSD3B1, HSD3B2, SRD5A1, SRD5A2 and 4 morecytosol