Dimethylcurcumin (ASC-J9, CAS 52328-98-0, C₂₃H₂₄O₆, MW ~396.43 g/mol) is a synthetic curcuminoid derivative and selective androgen receptor (AR) degrader. Unlike AR antagonists (enzalutamide, bicalutamide) that competitively block the AR ligand-binding domain, ASC-J9 uses a post-translational mechanism: it binds to AR, promotes AR ubiquitination through enhanced E3 ligase recruitment, and targets AR for proteasome-mediated degradation. This selectively reduces AR protein levels without altering AR mRNA transcription — confirmed by unchanged AR mRNA on qRT-PCR while AR protein drops on Western blot. ASC-J9 does not affect other steroid hormone receptors (ER, PR, GR, MR), demonstrating high receptor selectivity. The 3,4-dimethoxy substitution on both phenyl rings blocks Phase II glucuronidation and sulfation conjugation — the metabolic pathways that rapidly clear natural curcumin (t₁/₂ ~0.1–0.2 h). This extends ASC-J9 plasma half-life to ~1.5–2 h (~10× improvement). UPOR Biotech provides ASC-J9 at ≥98% HPLC (Research Grade) with ≥99% available.

ASC-J9 has demonstrated preclinical efficacy across five AR-driven disease research areas. (1) Castration-resistant prostate cancer (CRPC): ASC-J9 suppresses AR target genes (PSA, TMPRSS2), induces G1 cell cycle arrest and apoptosis in AR-positive prostate cancer cell lines (LNCaP, C4-2, 22Rv1) — including enzalutamide-resistant models — and reduces tumor xenograft growth in mouse models. (2) Androgenetic alopecia: topical ASC-J9 promotes hair regrowth in testosterone-induced alopecia mouse models by degrading AR in dermal papilla cells, which interrupts the AR → TGF-β1 → catagen (hair follicle regression) signaling cascade. (3) Acne vulgaris: AR degradation in sebocytes reduces sebum production — a mechanism-based research approach to acne pathogenesis. (4) Spinal bulbar muscular atrophy (SBMA / Kennedy disease): ASC-J9 degrades polyglutamine-expanded mutant AR aggregates that drive neurodegeneration in this inherited condition — preclinical studies show reduced aggregate burden and improved motor function. (5) AR-positive breast cancer: emerging data suggests efficacy where AR functions as an oncogenic driver. All applications are for laboratory research use only — not for human or veterinary therapeutic use.

The defining advantage of ASC-J9 over natural curcumin is its ~10× extended plasma half-life — achieved through a single critical structural modification. Natural curcumin contains free phenolic hydroxyl (-OH) groups on its phenyl rings that undergo rapid Phase II metabolism — glucuronidation by UGT enzymes and sulfation by SULT enzymes — resulting in extensive first-pass metabolism, a plasma half-life of only ~0.1–0.2 hours, and virtually undetectable systemic levels after oral administration. ASC-J9 replaces these -OH groups with methoxy (-OCH₃) groups (3,4-dimethoxy substitution), effectively blocking the primary metabolic conjugation sites. This extends plasma half-life to ~1.5–2 hours (~10× improvement), maintains detectable systemic concentrations after oral administration in preclinical models, and improves tissue distribution. Beyond bioavailability, ASC-J9 introduces a distinct pharmacological mechanism — selective AR protein degradation via the ubiquitin-proteasome pathway — that natural curcumin does not possess. ASC-J9 also demonstrates improved chemical stability, photostability, and cellular membrane permeability versus natural curcumin. For in vivo AR-targeting research, ASC-J9 is the preferred curcuminoid scaffold because it provides both the bioavailability and the mechanism that natural curcumin lacks.

UPOR Biotech provides Dimethylcurcumin (ASC-J9) in two purity grades to match research requirements. Research Grade (≥98% HPLC) — the standard grade suitable for routine in vitro assays (cell viability, Western blot, qRT-PCR, reporter gene assays), biochemical studies (AR binding, ubiquitination assays), and preclinical in vivo models. This is the most commonly ordered grade. High Purity Grade (≥99% HPLC) — recommended for sensitive quantitative applications including dose-response pharmacology studies, reference standard preparation, publication-quality research, and any application where maximum purity confidence is required. Both grades are supplied with full analytical documentation: Certificate of Analysis (COA) with HPLC purity, retention time, and full impurity profile; signed and dated HPLC chromatogram; ¹H NMR spectrum; mass spectrum (ESI+); MSDS; and lot-specific quality data. Each batch undergoes rigorous QC including HPLC purity analysis (area normalization, 254 nm), identity confirmation (NMR, MS), residual solvent testing per ICH Q3C, heavy metals analysis (Pb, As, Hg, Cd), and microbial limits testing per USP <61>/<62>. Packaging: 10 mg to 1 g amber glass vials with PTFE-lined caps. MOQ: 10 mg. Free sample available for qualified research institutions.

Every shipment of Dimethylcurcumin (ASC-J9) includes a comprehensive documentation package: Certificate of Analysis (COA) with HPLC purity (≥98% or ≥99%), retention time, full impurity profile, heavy metals (≤10 ppm total; Pb ≤2 ppm, As ≤1 ppm, Hg ≤1 ppm, Cd ≤1 ppm), residual solvents per ICH Q3C, and microbial limits per USP <61>/<62>; Material Safety Data Sheet (MSDS); Signed and dated HPLC Chromatogram; ¹H NMR Spectrum confirming structural identity; Mass Spectrum (ESI+); BSE/TSE-Free Statement; Non-GMO Statement; Allergen Statement; HALAL Certificate; KOSHER Certificate; ISO 22000 + HACCP; ISO 9001:2015; FDA Facility Registration; Stability Data (-20°C real-time 24-month and accelerated 40°C/75%RH 6-month); and Complete Lot Traceability from raw material to finished product. All documents provided in English. Free sample available for qualified B2B buyers and research institutions. MOQ: 10 mg.