1-Hydroxyethyl 4,5-Diamino Pyrazole Sulfate

AKA: 155601-30-2, 5-Diamino-1-(2-hydroxyethyl)pyrazole sulfate, Colorex WP5, 1H-Pyrazole-1-ethanol, Sulfate (1:1), 1-(2-Hydroxyethyl)-4, 5-diaminopyrazole sulfate, 5-Diamino-1-(2-hydroxyethyl)-1H-pyrazole sulfate, Sulfate (1:1) (salt)

Synthetic

Not Clean

1H-Pyrazole-1-Ethanol, 4,5 diamino-, sulfate; 1-(2-hydroxyethyl)-1H-pyrazol-4,5-diyldiammoniumsulfate

Formula

C5H12N4O5S

Mol. Weight

240.24

CAS #

155601-30-2

Form

Powder

Functions

Hair Dyeing

Colors Hair

Traditional Use

A synthetic compound developed in the late 20th century specifically for use as a hair dye precursor. Created to provide stable, predictable color results in hair coloring products.

EWG

CIR

Safe as used

Pregnancy

Caution

CIR Safety Findings

ewg-4

medical-approval

all-shades-safe

Regulatory Status

USA✔ permitted

EU⚠ restricted

JAPAN⚠ restricted

CANADA⚠ restricted

Regulatory Agencies

EWG CIR FDA EU COSING Health Canada

Skin Types

●all-skin-types

Best For

General

Pregnancy & Breastfeeding Safe

Caution

The paper trail

🔬Peer-reviewednone on file

⚖️Regulatory1 listing →

🛡️Safety-assessed3 reviews →

Counts, not a verdict. A listing isn't a study. The trail, you decide.

Verified Jun 2026

Data: PubChem · CosIng · EWG · CIR