1. Basic Information

• Chinese Name: Wang Resin / Polybenzyloxybenzyl alcohol resin / [4‑(Hydroxymethyl)phenoxymethyl]polystyrene
• English Name: Wang Resin, 4‑Benzyloxybenzyl alcohol resin, HMP Resin
• CAS No.: 201058‑08‑4
• MDL No.: MFCD00131778
• Support Matrix: Divinylbenzene (DVB) cross‑linked polystyrene beads (1% DVB cross‑linking as standard; 2% cross‑linking is also available)
• Linker: p‑alkoxybenzyl alcohol; terminal functional group: benzyl hydroxyl group (–CH₂OH)

2. Appearance & Typical Specifications

• Physical State: Off‑white / pale beige insoluble resin microspheres
• Mesh Size: Common grades: 100‑200 mesh, 200‑400 mesh
• Loading Capacity: Commercial typical range 0.4～1.2 mmol/g (0.8‑1.0 mmol/g is the most widely used grade)
• Swelling Property: Good swelling in dichloromethane (DCM) and DMF (4‑8 mL/g), suitable for solvent systems in solid‑phase peptide synthesis

3. Key Chemical Properties

1. The hydroxyl group forms an ester bond with the first Fmoc‑protected amino acid to anchor the C‑terminus of the peptide chain.
2. The linker is acid‑labile: cleavage with trifluoroacetic acid (90‑95% TFA) releases peptides with a free carboxylic acid at the C‑terminus.
3. Stable under Fmoc deprotection (piperidine, weak base) and coupling conditions without premature cleavage.
4. Tolerant to most solid‑phase synthesis reagents; one of the classic solid supports for the Fmoc synthetic strategy.

4. Main Applications

1. Fmoc‑based Solid‑Phase Peptide Synthesis (SPPS) for peptides with a C‑terminal carboxylic acid.
2. Preparation of short peptides, pharmaceutical peptides, peptide APIs and peptide fragments for R&D.
3. Solid‑phase synthesis of small organic molecules and construction of combinatorial chemical libraries.

Note for comparison: Wang resin yields peptides with C‑COOH, while Rink Amide resin produces peptides with a C‑terminal carboxamide (‑CONH₂) after cleavage.

5. Storage & Handling

• Storage: Keep tightly sealed under dry conditions, store at 2‑8 °C away from light and moisture.
• Operation: Handle in a fume hood; avoid inhalation of fine resin dust.
• Cleavage reagent: Concentrated TFA is highly corrosive; wear full personal protective equipment.

6. Safety Overview