A second monoclinic polymorph of 1-benzyl-N-methyl-1H-pyrrole-2-carboxamide

In the title compound, C13H14N2O, the Npyrrole—C(H2)—C—C torsion angle is −7.7 (3)° and the dihedral angle between the pyrrole and benzene rings is 83.6 (2)°. In the crystal, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains extending along the c axis. We have previously reported another polymorphic form of this title compound, which has the same space group with different cell parameters: a = 9.8285 (18) Å, b = 23.588 (4) Å, c = 9.9230 (17) Å, β = 90.107 (3)°, Z = 8 and V = 2300.5 (7) Å3 [Zeng et al. (2010 ▶). Acta Cryst. E66, o2051]

rac-Dimethyl 2-(1H-pyrrole-2-carboxamido)­butane­dioate

The title compound, C11H14N2O5, was synthesized by condensation of (RS)-2-amino­succinic acid dimethyl ester with 2-trichloro­acetyl­pyrrole at room temperature. The amide group is twisted by 7.4 (1)° from the plane of the pyrrole ring. In the crystal, mol­ecules are linked by inter­molecular N—H⋯O hydrogen bonds into chains extending along the c axis

Adversarial Multimodal Representation Learning for Click-Through Rate Prediction

For better user experience and business effectiveness, Click-Through Rate (CTR) prediction has been one of the most important tasks in E-commerce. Although extensive CTR prediction models have been proposed, learning good representation of items from multimodal features is still less investigated, considering an item in E-commerce usually contains multiple heterogeneous modalities. Previous works either concatenate the multiple modality features, that is equivalent to giving a fixed importance weight to each modality; or learn dynamic weights of different modalities for different items through technique like attention mechanism. However, a problem is that there usually exists common redundant information across multiple modalities. The dynamic weights of different modalities computed by using the redundant information may not correctly reflect the different importance of each modality. To address this, we explore the complementarity and redundancy of modalities by considering modality-specific and modality-invariant features differently. We propose a novel Multimodal Adversarial Representation Network (MARN) for the CTR prediction task. A multimodal attention network first calculates the weights of multiple modalities for each item according to its modality-specific features. Then a multimodal adversarial network learns modality-invariant representations where a double-discriminators strategy is introduced. Finally, we achieve the multimodal item representations by combining both modality-specific and modality-invariant representations. We conduct extensive experiments on both public and industrial datasets, and the proposed method consistently achieves remarkable improvements to the state-of-the-art methods. Moreover, the approach has been deployed in an operational E-commerce system and online A/B testing further demonstrates the effectiveness.Comment: Accepted to WWW 2020, 10 page

2-Iodo-5-nitro­thio­phene

The title compound, C4H2INO2S, was synthesized by nitration of iodo­thio­phene with acetyl nitrate. The molecule is essentially planar, withthe nitro group tilted by 1.78 (19)° and the iodine atom displaced by 0.0233 (2) Å with respect to the thiophene ring. In the crystal structure, adjacent mol­ecules are linked through weak I⋯O inter­actions [3.039 (2)Å], forming chains extending along the b axis

1H-Pyrrole-2-carboxylic acid

In the title compound, C5H5NO2, the pyrrole ring and its carboxyl substituent are close to coplanar, with a dihedral angle of 11.7 (3)° between the planes. In the crystal structure, adjacent mol­ecules are linked by pairs of O—H⋯O hydrogen bonds to form inversion dimers. Additional N—H⋯O hydrogen bonds link these dimers into chains extending along the a axis

Methyl 3-[(1-butyl-1H-indol-3-yl)carbonyl­amino]propionate

In the title mol­ecule, C17H22N2O3, the mean plane of the terminal (C=O)OMe fragment and the indole plane form a dihedral angle of 78.94 (3)°. Inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains extended along the c axis. The crystal packing exhibits π–π inter­actions, indicated by the short distance of 3.472 (2) Å between the centroids of the five-membered heterocycles of neighbouring mol­ecules

1-Ethyl-1H,6H-pyrrolo[2,3-c]azepine-4,8(5H,7H)-dione

The title compound, C10H12N2O2, was synthesized by cyclization of 3-(1-ethyl­pyrrole-2-carboxamido)propanoic acid in the presence of polyphospho­ric acid and diphospho­rus pentoxide. In the crystal structure, adjacent mol­ecules are linked by N—H⋯O hydrogen bonds, forming chains extending along the b axis

Methyl (1H-pyrrol-2-ylcarbonyl­amino)acetate

In the crystal structure of the title compound, C8H10N2O3, mol­ecules are linked by N—H⋯O hydrogen bonds, forming ribbons of centrosymmetric dimers extending along the c axis