The complestatins as HIV-1 integrase inhibitors. Efficient isolation, structure elucidation, and inhibitory activities of isocomplestatin, chloropeptin I, new complestatins, A and B, and acid-hydrolysis products of chloropeptin I.
From the screening of a microbial extract library, isocomplestatin (1), a new axial-chiral isomer of complestatin (2) which is a known rigid bicyclic hexapeptide, was identified as a potent natural product inhibitor of HIV-1 integrase, a unique enzyme responsible for viral replication. Isocomplestatin showed inhibitory activities (IC(50)) in coupled 3'-end processing/strand transfer (200 nM), strand transfer (4 microM), and HIV-1 replication (200 nM) in virus-infected cells. Attempted large-scale isolation of 1 by the literature method, used for the isolation of complestatin, led to lower yield and limited availability. We have developed several new, two-step, high-yielding absorption/elution methods of isolation based on reverse-phase chromatography at pH 8 that are applicable to scales from one gram to potential industrial quantities. We have also discovered and determined the structure of two new congeners of 1, namely, complestatins A (4) and B (5), with almost equal HIV-1 integrase activity. They differ from 1 at C2' and C3' of the tryptophan moiety (residue F). Selective acid hydrolysis of chloropeptin I (3), itself a known acid-catalyzed rearranged isomer of 1 and 2 (8'- vs 7'-substitution in tryptophan residue F, respectively), an isomer of complestatin, and isocomplestatin resulted in a number of fragments (6-10) with retention of most of the HIV-1 integrase activity. The structure-activity relationship as revealed by these compounds could possibly lead to the design of better inhibitors or understanding of the HIV-1 integrase target.
Singh
S B
SB
Merck Research Laboratories, P.O. Box 2000, Rahway, New Jersey 07065, USA. sheo_singh@merck.com
Jayasuriya
H
H
Salituro
G M
GM
Zink
D L
DL
Shafiee
A
A
Heimbuch
B
B
Silverman
K C
KC
Lingham
R B
RB
Genilloud
O
O
Teran
A
A
Vilella
D
D
Felock
P
P
Hazuda
D
D
D019380:Anti-HIV Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002733:Chlorophenols / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D008401:Gas Chromatography-Mass Spectrometry; D015699:HIV Envelope Protein gp120 / Q000378:metabolism; D019427:HIV Integrase / Q000378:metabolism*; D019428:HIV Integrase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D015497:HIV-1 / Q000201:enzymology* / Q000378:metabolism; D017493:Leukocyte Common Antigens / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010456:Peptides, Cyclic; D013237:Stereoisomerism; D013302:Streptomyces / Q000737:chemistry / Q000378:metabolism; D013329:Structure-Activity Relationship
D019380:Anti-HIV Agents; D002733:Chlorophenols; D015699:HIV Envelope Protein gp120; D019428:HIV Integrase Inhibitors; D009842:Oligopeptides; D010456:Peptides, Cyclic; C023490:complestatin; D019427:HIV Integrase; D017493:Leukocyte Common Antigens