SG85

CHEBI:147346 ·resolve ·ANTIVIRAL ·EXACT REVIEWED

A secondary carboxamide resulting from the formal condensation of the carboxy group of N-[(benzyloxy)carbonyl]-O-tert-butyl-L-serine with the primary amino group of ethyl (2E,4S)-5-[(3S)-2-oxopyrrolidin-3-yl]-4-(L-phenylalanylamino)pent-2-enoate. It is a potent enterovirus 3C protease inhibitor with EC50 of 180 nM against enterovirus 71 (EV71) and 60 nM against human rhinovirus 14 in a live virus-cell-based assay. — ChEBI

Classification

Strictly broader compounds or drug classes this molecule belongs to.

Label unavailable CHEBI:140325
Label unavailable CHEBI:23990
Label unavailable CHEBI:25698
Label unavailable CHEBI:51702
Label unavailable CHEBI:74223
Label unavailable CHEBI:84135
Label unavailable CHEBI:84144
Label unavailable CHEBI:90628

Chemical structure

Computed structure properties
Molecular formula	C35H46N4O8
Charge	0
Average mass	650.773 Da
Monoisotopic mass	650.33156 Da
Source	ChEBI
InChIKey	CTAXDRJNQQBEIB-VCJIVHKYSA-N

SMILES

CCOC(=O)/C=C/[C@H](C[C@@H]1CCNC1=O)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](COC(C)(C)C)NC(=O)OCc1ccccc1

InChI

InChI=1S/C35H46N4O8/c1-5-45-30(40)17-16-27(21-26-18-19-36-31(26)41)37-32(42)28(20-24-12-8-6-9-13-24)38-33(43)29(23-47-35(2,3)4)39-34(44)46-22-25-14-10-7-11-15-25/h6-17,26-29H,5,18-23H2,1-4H3,(H,36,41)(H,37,42)(H,38,43)(H,39,44)/b17-16+/t26-,27+,28-,29-/m0/s1

Also called

N-[(benzyloxy)carbonyl]-O-tert-butyl-L-seryl-N-{(2S,3E)-5-ethoxy-5-oxo-1-[(3S)-2-oxopyrrolidin-3-yl]pent-3-en-2-yl}-L-phenylalaninamide (EXACT_SYNONYM)— chebi
SG 85 (EXACT_SYNONYM)— chebi
SG-85 (EXACT_SYNONYM)— chebi

Cross-references

Identifiers for this same structure in other resources. An accession that lands on two different structures in this corpus is withheld from both rather than shown here, since it names at most one of them.

cas:1575662-24-6

Activity roles

Every antimicrobial role a source asserts for this compound — the unreduced evidence behind its antimicrobial_class.

anticoronaviral agent CHEBI:149553
antiviral agent CHEBI:22587

Source concepts

Every upstream concept that resolved to this record. The merge is the product: this is what shows ChEBI and CARD are describing the same structure.

Upstream concepts merged into this record
Source	Native ID	Label	Minted CURIE	Version
CHEBI	`CHEBI:147346`	SG85	`antibioticmech:chebi-d909953997`	2026-08-30

Molecular targets

The molecular entity or process this compound acts on. Each target carries evidence — this is a mechanistic claim, not a classification.

picornavirus 3C protease VIRAL_PROTEIN DIRECT_BINDING_TARGET

Structure-guided inhibitor design included crystal structures of inhibitor complexes and inhibition of purified enterovirus 68 3C protease. SG85 was the most potent compound and also blocked enterovirus and rhinovirus replication. Evidence status: PRIMARY_EVIDENCE. Source: PRIMARY_LITERATURE 2013-02 (retrieved 2026-09-02).

PMID:23388726 (Primary structural, biochemical, and infected-cell study.)
PMID:26055377 (Primary rhinovirus study; reverse genetics placed both required low-level-resistance substitutions in 3C protease.)

Mechanism summary

Mode of action: VIRAL_PROTEASE_INHIBITION microbial target — CURATOR: PMID:23388726 reports structure-guided design, crystal structures of inhibitor complexes with enterovirus 68 3C protease, purified-protease inhibition, and SG85 activity against multiple picornaviruses. PMID:26055377 independently linked SG85 resistance substitutions to rhinovirus 3C protease by reverse genetics.

Resistance mechanisms

1 source-backed resistance determinants or associations, with ARO grounding where reported. Grouped by reported mechanism type.

ANTIBIOTIC_TARGET_ALTERATION 1

ANTIBIOTIC_TARGET_ALTERATION
Determinant	ARO ID	Organism	Gene families	Evidence
rhinovirus 3C protease S127G and T143A substitutions Both substitutions were required for the low-level SG85 resistance phenotype selected in vitro and confirmed by reverse genetics.	—	not organism-specific	picornavirus 3C protease	PMID:26055377 (Primary selection and reverse-genetics study.)

Record-level evidence

PMID:23388726 (Primary SG85 design, target, and antiviral-activity study.)
PMID:25199773 (Primary in-vitro activity study across 21 enterovirus 71 strains or isolates.)
PMID:26055377 (Primary rhinovirus activity and target-linked resistance study.)

Curation history

SEEDED_FROM_SOURCES 2026-08-30 · seed_from_sources
Seeded from data/raw/ inventories (CHEBI)
RESEEDED_FROM_SOURCES 2026-08-30 · seed_from_sources
Re-seeded from updated data/raw/ inventories
RESEEDED_FROM_SOURCES 2026-08-30 · seed_from_sources
Re-seeded from updated data/raw/ inventories
REVIEWED 2026-09-02 · codex · LLM-assisted
Verified exact ChEBI identity, structure, and antiviral class; replaced the mismatched SARS-coronavirus role rationale with compound-specific picornavirus 3C-protease evidence, added the target, and captured target-alteration resistance demonstrated by reverse genetics.

Provenance

Seeded by scripts/seed_from_sources.py from the committed inventories in data/raw/. View the record (YAML).

Explore across X-Mech: MediaIngredientMech (SG85) · CultureMech · NaturalProductMech · PathwayMech · TraitMech